Seal for a seed metering system

ABSTRACT

A seed metering system for metering a plurality of seeds includes a meter housing having a front side and a rear side opposite and attached to the front side, a seed inlet defined within the front side of the meter housing, and a seed disk positioned within and rotatable relative to the meter housing. The seed disk has a first side in facing relation to the front side of the meter housing and a second side in facing relation to the rear side of the meter housing. The seed metering system further includes a seal in contact with the front side of the meter housing and the first side of the seed disk.

BACKGROUND

The present disclosure relates to a seeding system and more particularlyto a seed meter and the associated system for controlling the flow ofseeds.

SUMMARY

Current seeding practices tend to involve one of two types of seedingsystems: planters and air seeders. Planters generally singulate orindividually meter seeds prior to planting and are generally used todisperse seeds where precise placement is required for maximum yield andthe seeding rate permits use of singulating technologies. Air seedersgenerally meter seeds volumetrically and are generally used in high rateseeding applications and where precise seed placement is of lessimportance or not practical due to the high rates.

The invention provides, in one aspect, a seed metering system formetering a plurality of seeds. The seed metering system includes a meterhousing having a front side and a rear side opposite and attached to thefront side, a seed inlet defined within the front side of the meterhousing, and a seed disk positioned within and rotatable relative to themeter housing. The seed disk has a first side in facing relation to thefront side of the meter housing and a second side in facing relation tothe rear side of the meter housing. The seed metering system furtherincludes a seal in contact with the front side of the meter housing andthe first side of the seed disk.

The invention provides, in another aspect, a seed metering system formetering a plurality of seeds. The seed meter includes a meter housinghaving a first side and a second side opposite and attached to the frontside, a seed disk mounted within and rotatable relative to the meterhousing, and a seal. The seal includes a first layer in contact with thefirst side of the meter housing, a second layer fixed to the firstlayer; the second layer having a higher compressibility than the firstlayer, and a low friction coating applied to the second layer. The lowfriction coating is configured to contact the seed disk.

The invention provides, in yet another aspect, an interface. Theinterface includes a seed meter disk having a first face and a secondface opposite the first face, and an axial thickness definedtherebetween. The interface further includes a plurality of seedopenings extending from the first face to the second face, and a sealextending around at least a portion of the seed meter disk. The seedmeter disk is configured to rotate relative to the seal. The seal is insliding contact with the first planar face of the seed meter disk.

The invention provides, in yet another aspect, a seal for a seed meterhousing. The seal includes a rigid back plate having a first side and asecond side, with an engagement feature located on the first side, and acompressible elastomeric foam having a first side and a second side, thefirst side of the compressible elastomeric foam attached to the secondside of the rigid back plate.

Other features and aspects of the disclosure will become apparent byconsideration of the following detailed description and accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a vehicle having a plurality of seedmeters.

FIG. 2 is a perspective view of one of the seed meters shown in FIG. 1.

FIG. 3 is another perspective view of one of the seed meters shown inFIG. 1.

FIG. 4 is a perspective view of a cutaway of the seed meter, showing ametering member mounted on a hub.

FIG. 5A is an exploded view of the metering member and the hub accordingto one embodiment.

FIG. 5B is an exploded view of the metering member and the hub accordingto another embodiment.

FIG. 6 is a cross-sectional view of the interface between the meteringmember and the hub.

FIG. 7 is a perspective view of the seed meter with a portion of themeter housing removed to reveal a seed meter disk and seed singulatoraccording to one embodiment of the present disclosure.

FIG. 8 is a front view of the seed meter with in situ singulator of FIG.7.

FIG. 9 is a cross-section of the seed meter taken through a central axisof the seed meter disk and hub.

FIG. 10 is a cross-section of the seed meter taken through a planeoffset from and parallel to the central axis.

FIG. 11 is a perspective view of the seed meter with an opposite portionof the meter housing removed as compared to FIGS. 7 and 8, and with theseed meter disk removed, revealing a side of the singulator that facesthe seed meter disk.

FIG. 12 is an exploded assembly view of the singulator removed from asingulator biasing spring that is secured to the meter housing.

FIG. 13 is an exploded assembly view of the biasing spring and a backside of the singulator that cooperates with the biasing spring.

FIG. 14 is a perspective view of the singulator of FIGS. 7 to 13, asviewed from the back side thereof.

FIG. 15 is a perspective view of a chamfer portion of the singulatoroverlying the seed agitator recesses in the seed meter disk.

FIG. 16 is a front view of a seed meter disk and singulator according toanother embodiment of the disclosure.

FIG. 17 is a perspective of a notched brush portion of the singulator ofFIG. 16.

FIG. 18 is a perspective view of a seed meter disk and singulatoraccording to yet another embodiment of the disclosure

FIG. 19 is a side view of a plurality of singulator brushes of thesingulator of FIG. 18.

FIG. 20 is a perspective view illustrating a first flexible seal havingfirst and second layers.

FIG. 21 is a perspective view of the first flexible seal, showing thefirst layer.

FIG. 22 is a perspective view of the first flexible seal, showing thesecond layer.

FIG. 23 is a front view of the first flexible seal and a second flexibleseal relative to a seed meter.

FIG. 24 is a partial cross-sectional view of the flexible seal withrespect to the seed meter.

FIG. 25 is a perspective view of the first flexible seal relative to theseed meter.

FIG. 26 is another perspective view of the first flexible seal relativeto the seed meter.

FIG. 27 is a perspective view illustrating a first flexible sealaccording to another embodiment, the first flexible seal having prongs.

FIG. 28 is a side view of one of the prongs shown in FIG. 27.

FIG. 29 is a side view of an exemplary air seeding row unit having aseed sensor according to one embodiment of the present disclosure.

FIG. 30 is a rear view of a left-hand opener air seeding row unitaccording to the embodiment shown in FIG. 29.

FIG. 31 is a rear view of a right-hand opener air seeding row unitaccording to the embodiment shown in FIG. 29.

FIG. 32 is a detail rear view of an upper portion of the seed sensorhaving angled support surfaces to enable the configurations of bothFIGS. 30 and 31.

FIG. 33 is a perspective view of an upper portion of the seed sensor,illustrating a loop thereof engaged with a portion of the row unitframe.

FIG. 34 is a side view of another exemplary air seeding row unit havingthe seed sensor of FIGS. 29-33.

FIG. 35 is a perspective view of the seed sensor, illustrating themounting configuration with the bracketry of the air seeding row unit.

FIG. 36 is a cross-section view of the mounted seed sensor, taken alongline 36-36 of FIG. 35.

FIG. 37 is a perspective view of an upper portion of the seed sensormounted on the frame of the air seeding row unit of FIG. 34.

FIG. 38 is a perspective view of the seed sensor, including an optionalsnap-on adapter for in-line mounting.

FIG. 39 is a cross-section of the seed sensor, taken along line 39-39 ofFIG. 38.

FIG. 40 is another cross-section of the seed sensor, identical to FIG.39 except for the snap-on adapter being shown with a clip thereof beingreleased from the seed sensor loop.

FIG. 41 is a perspective view of a seed meter having a seed meterhousing rotated out of an operational position relative to a supportstructure.

FIG. 42 is a perspective view of the seed meter housing of FIG. 1A inthe operational position.

FIG. 43 is a side view of a motor, a motor output shaft, and a mountingbracket of the seed meter of FIG. 1.

FIG. 44 is a perspective view of a release lever of the seed meter ofFIG. 1.

FIG. 45 is a perspective view of a pivot point of the seed meter housingof FIG. 1 relative to the mounting bracket.

FIG. 46 is a perspective view of a seed side of the seed disk housingincluding a nose for engaging the mounting bracket.

FIG. 47 is a perspective view of the mounting bracket and the motoroutput shaft.

FIG. 48A is a partial side view of the seed side of the seed diskhousing illustrating the mounting bracket mating surface.

FIG. 48B is a partial side view of the mounting bracket illustrating theseed disk housing mating surface.

FIG. 49 is a perspective view of a seed meter disk having an agitatorstructure according to one embodiment of the present disclosure.

FIG. 50A is a section view through a seed meter having a seed diskhousing with drain holes.

FIG. 50B is a schematic illustration of the arrangement of the drainholes.

FIG. 51 is a section view through the seed meter, transverse to the viewshown in FIG. 1.

FIG. 52 is a perspective cross-sectional view of the seed meter.

FIG. 53 is a side view of the seed meter shown in FIG. 3.

FIG. 54 is a perspective view of the seed meter mounted to a supportingstructure.

FIG. 55 is a perspective view of a pair of seed port connectors of theseed meter according to one embodiment of the disclosure.

FIG. 56 is a perspective view of a hose connector piece operable withone of the seed port connectors of FIG. 55 to form a tool-lessquick-connect coupling.

FIG. 57 is a side view of the attached quick-connect coupling.

FIG. 58 is a side view of an alternate embodiment of the quick-connectcoupling in which the second connector piece is a plug rather than aconduit for hose attachment.

FIG. 59 is a detail view of the quick-connect coupling of FIG. 57 orFIG. 58, illustrating a pin-slot interface and ramp angles formed by theslot.

FIG. 60 is a cross-section of a seed meter housing and seed singulatoraccording to another embodiment of the present disclosure.

FIG. 61 is a perspective view of a biasing spring for the seedsingulator positioned in the seed meter housing of FIG. 60.

FIG. 62 is a perspective view of the seed singulator assembled with thespring of FIGS. 60-61.

FIG. 63 is a perspective view of a biasing spring and seed singulatoraccording to another embodiment of the present disclosure.

FIG. 64 is a bottom view of the biasing spring and seed singulator ofFIG. 63.

FIG. 65 is a front view of the seed singulator of FIGS. 63-64 in apre-assembly position with respect to the biasing spring and seed meterhousing.

FIG. 66 is a front view of the seed singulator of FIGS. 63-65 in anassembled position with respect to the biasing spring and seed meterhousing.

FIG. 67 is a front view of a biasing spring in a seed meter housing fora seed singulator according to another embodiment of the presentdisclosure.

FIG. 68 is a perspective view of the biasing spring of FIG. 67 assembledwith a seed singulator.

FIG. 69 is a front view of the seed singulator of FIG. 68 in apre-assembly position with respect to the biasing spring and seed meterhousing.

FIG. 70 is a front view of the seed singulator of FIGS. 68-69 in anassembled position with respect to the biasing spring and seed meterhousing.

Before any embodiments of the disclosure are explained in detail, it isto be understood that the disclosure is not limited in its applicationto the details of construction and the arrangement of components setforth in the following description or illustrated in the accompanyingdrawings. The disclosure is capable of supporting other embodiments andof being practiced or of being carried out in various ways. Also, it isto be understood that the phraseology and terminology used herein is forthe purpose of description and should not be regarded as limiting.

DETAILED DESCRIPTION

FIG. 1 illustrates a work vehicle 10 according to example embodiments ofthe present disclosure. The work vehicle 10 may be towed by anothervehicle, such as a tractor. Thus, the work vehicle 10 may be a towedwork vehicle. In other embodiments, the work vehicle 10 of the presentdisclosure may be a self-propelled vehicle. In some embodiments, thework vehicle 10 may be an air cart or air seeder. It will be appreciatedthat the illustrated work vehicle 10 is an example embodiment. One ormore features of the present disclosure may be included on a differentwork vehicle, such as a planter, a commodity cart, or other work vehiclewithout departing from the scope of the present disclosure.

The work vehicle 10 includes a front end 14 and a rear end 16, and afore-aft axis 18 extends generally between the front and rear ends 14,16. The work vehicle 10 also includes a first side 20 and a second side22, and a lateral axis 24 extends generally between the first and secondsides 20, 22. A vertical axis 26 extends perpendicular to both thefore-aft axis 18 and the lateral axis 24.

Generally, the work vehicle 10 may include a chassis 11 and a pluralityof wheels 12. The chassis 11 may be a rigid frame that supports thecomponents described in detail below. The wheels 12 may support thechassis 11 and enable movement of the vehicle 10 across the field.

The work vehicle 10 may also include one or more commodity containers28. The container 28 may be supported on the chassis 11 and disposedproximate the rear end 16. Also, in some embodiments, the container 28may be disposed centrally between the first side 20 and the second side22. The commodity container 28 may contain seed, fertilizer, and/oranother particulate or granular commodity.

Additionally, the work vehicle 10 may include a metering system 30. Themetering system 30 may be a volumetric metering system. The meteringsystem 30 may be disposed generally underneath the commodity container28 in some embodiments. As such, particles of the commodity within thecontainer 28 may fall due to gravity toward the metering system 30. Themetering system 30 may operate to meter out the commodity from thecontainer 28 at a controlled rate as the vehicle 10 moves across thefield.

The work vehicle 10 may also include an airflow system 32. The airflowsystem 32 may include a fan 34 that generates a flow of air. The airflowsystem 32 may also include a plurality of airflow structures (e.g.,plenums, tubes, lines, etc.) that receive the air blowing from the fan34. Particles of the commodity (metered out by the metering system 30)may fall into the air stream and may flow to a distribution system 36.The distribution system 36 may include a plurality of hoses, lines, orother conduits that extend to different areas of the vehicle 10 alongthe lateral axis 24. The particles of the commodity may be propelled bythe airstream through the distribution system 36, to a plurality ofindividual row units 45 and to the soil. Each row unit 45 of the vehicle10 may include a seed meter 44 for singulating the commodity (e.g.,seeds) and a ground system 38 with openers, tillers or other similarimplements that prepare the soil for delivery of the seed, fertilizer,or other commodity delivered by the distribution system 36.

Moreover, the work vehicle 10 may include a control system 40. Thecontrol system 40 may be in communication with and may be configured forcontrolling the metering system 30, the airflow system 32, and/or othercomponents of the work vehicle 10. The control system 40 may be whollysupported on the work vehicle 10, or the control system 40 may includecomponents that are remote from the vehicle 10. The control system 40may be in electronic, hydraulic, pneumatic, mechanical, or othercommunication with the metering system 30, the airflow system 32, etc.In some embodiments, the control system 40 may be in communication withactuators, sensors, and/or other components of the work vehicle 10.

During operation of the work vehicle 10 (e.g., when towed by a tractoror other towing vehicle across a field), the commodity may fall from thecontainer 28 toward the metering system 30. The control system 40 maycontrol the metering system 30 (e.g., by controlled actuation of a driveunit), which allows a controlled quantity of particles to pass into theairflow system 32 at a predetermined rate. The control system 40 mayalso control the fan 34 for generating a continuous airstream that blowsthrough the airflow system 32, receives the particles metered out fromthe metering system 30, and flows through the distribution system 36across the work vehicle 10 to the soil.

As shown in FIGS. 2-4, the seed meter 44 includes a mini hopper 50, aseed disk housing 52 supporting a metering member such as a seed meterdisk (or simply seed disk 54, shown at least in FIG. 4) and a singulator56 (shown at least in FIG. 7), and a motor 72 for driving the seed disk54.

The mini-hopper 50 is a receptacle that accepts seeds or otheragricultural product from the storage tank 28 (and the volumetric meter30) via a seed inlet 60. As shown, the seed inlet 60 is located adjacentto the top of the mini-hopper 50 such that seeds entering themini-hopper 50 are directed by gravity to a seed outlet or seed diskhousing inlet 62 (FIG. 4). The mini-hopper 50 further includes an airinlet 64 positioned adjacent to the seed inlet 60 and operable toprovide an airflow through the mini-hopper 50 and into the seed diskhousing 52.

The seed disk housing 52 is formed in two halves, a front or seed sideof the seed disk housing 52A and a rear or vacuum side of the seed diskhousing 52B. The seed disk 54 is housed therebetween. A hub 66 isrotatably mounted within bearings 68A, 68B positioned within a cavity oraperture 58 in the rear side of the seed disk housing 62B and defines anaxis of rotation 68. The seed disk 54 is mounted to the hub 66 androtates therewith about the axis of rotation 68.

The seed disk 54 is a gear (e.g., a spur gear) defined by a wheel havingradially extending teeth 54A, a seed-side face 54B, and a vacuum-sideface 54C. A first cavity 46 is defined within the seed disk housing 52between the seed side of the seed disk housing 52A and the seed disk 54.A second cavity 48 is defined within the seed disk housing 52 betweenthe vacuum side of the seed disk housing 52B and the seed disk 54. Bothof the faces 54B, 54C are generally planar, though they can deviate fromplanar to define apertures (such as apertures 78, 112, 120 and agitatorpockets 220 as described below) and to accommodate mounting to the hub66, as shown in FIGS. 5A-6. The teeth 54A mesh with teeth 70A of a motoroutput gear 70 (either directly or indirectly via an intermediate gear)such that actuation of the motor 72 rotates the motor output gear 70,thereby rotating the seed disk 54 about the axis of rotation 68. Themotor 72 and the output gear 70 represent one embodiment of a seed meterdrive unit that is selectively energized to drive rotation of the seeddisk 54. Rotation of the seed disk 54 can be carried out in a single,predefined rotational direction R by the drive unit. The seed disk 54further includes a plurality of seed openings 78 located on theseed-side face 54B and extending at least partially through to thevacuum-side face 54C such that each seed opening 78 defines a passagethrough the seed disk 54. The seed openings 78 may be adapted for aparticular predetermined seed type so that the seeds, which are largerthan the seed openings 78 so as not to pass through the seed openings78, can be retained against the seed openings 78 and carried away fromthe seed pool as the seed disk 54 rotates. The seed openings 78 areprovided in a circumferential array along the seed disk 54. The spacingof the seed openings 78 may be even or uneven, although a fullcircumferential array of seed openings 78 with even spacing is herebyillustrated. Further, as shown in FIGS. 5A and 5B, the circumferentialarray of seed openings 78 may be arranged in more than one row, althougha single row is optional. As illustrated, each row of seed openings 78is located on the seed disk 54 at a single, fixed radial distance fromthe central axis of rotation 68. Seed agitators of various construction,such as the agitator pockets 220, may be located in a circumferentialarray at a radial position adjacent to the row(s) of seed openings 78.For example, FIGS. 5A and 5B illustrate a circumferential array ofagitators consisting of a single row of agitator pockets 220 formed inthe seed-side face 54B of the seed disk 54. The row of agitator pockets220 is located radially inward of the seed openings 78. The agitatorpockets 220 assist in stirring-up or agitating the seeds in the seedpool for encouraging seed retention within the seed openings 78 as theseed disk 54 rotates.

The rear side of the seed disk housing 52B includes an air outlet 80that is attachable to a vacuum source (not shown) to draw air fromwithin the rear side of the seed disk housing 52B, thereby creating apressure differential across the seed disk 54. The seed disk housing 52further includes a seed outlet or opening 82 for transferring the seedsand some air from the seed disk housing 52 and to the ground via anoutlet chute 84.

In operation, seeds are dispersed from the storage tank 38 to themini-hopper 50 via the distribution system 42, entering the mini-hopper50 through the seed inlet 60. The seeds collect within the mini-hopper50. The motor 72 is actuated by a controller 86 to rotate the seed disk54 (via the interface of meshing teeth 54A, 70A). Simultaneously, thevacuum source is actuated to create a pressure differential across theseed disk 54, thereby providing a suction force at the seed openings 78and holding the seeds against the seed openings 78 as the disk 54rotates. The singulator 56 knocks off extraneous seeds (those seeds notwithin one of the seed openings 78) such that each seed opening 78corresponds to a single seed. Once rotated past the singulator 56, theseeds are kicked out from the seed opening 78 and fall down the seedoutlet 82 and to the ground to be planted.

As shown in FIGS. 5A-6, the hub 66 is a cylindrical post having a headportion 90 and a body portion 92 separated by a round plate structure94. A cylindrical portion 90B of the head 90 includes an annular channel96 for engaging a resilient retention member such as an elastomericO-ring 98 (FIGS. 5A, 6) or a metal C-ring 100 (FIG. 5B). The head 90further includes a nose 90A formed as a truncated cone (i.e., conicalfrustum) centered on the rotational axis 68 of the hub 66. A first axialend 66A of the hub 66 is defined by the tip of the truncated cone, thefirst axial end 66A having a cross-sectional area (and diameter) that isless than the cross-sectional area (and diameter) of the base of thetruncated cone. The base of the truncated cone is similar incross-sectional area (and diameter) to the cylindrical portion 90B ofthe head 90, excepting for the decreased cross-sectional area of thechannel 96.

The body 92 of the hub 66 is cylindrical and has a diameter sized toengage the bearings 68A, 68B in the rear side of the seed disk housing52B. The body 92 extends from the head 90 (or from the plate structure94) to a second axial end 66B, opposite the first axial end 66A.Further, the body 92 includes a radial through hole 102 that extendstransverse to the rotational axis 68 adjacent to the second axial end66B of the hub 66. As shown in FIG. 4, a handle 104 is mounted on thesecond axial end 66B of the hub 66 to permit manual rotation of the hub66 relative to the seed disk housing 52. The handle 104 slides over thesecond axial end 66B of the hub 66, having an inner diameter seatedagainst the outer diameter of the body 92 of the hub 66. Once seated, anaperture (not shown) in the handle 104 is aligned with the through hole102 and a fastener 106 (e.g., a threaded fastener, a pin, a rivet, etc.)is positioned therein such that rotation of the handle 104 results inrotation of the hub 66. Alternatively, the handle may be affixed to thehub 66 without a fastener (e.g., press fit) or with an alternativefastener such as an adhesive.

As shown in FIG. 6, the hub 66 may include a collar 108 integrallyformed with the head 90 and the body 92 at a location between the head90 and the body 92. The collar 108 includes a larger circularcross-sectional area than the cross-sectional area of the body 92 andfunctions as a backstop for the plate structure 94. Further, the collar108 functions as a spacer between the plate structure 94 and the bearing68A.

The plate structure 94 is a generally flat circular plate and includes acentral aperture 94A (aligned with the rotational axis 68 whenassembled) for sliding over the head 90 of the hub 66. Once abuttedagainst the collar 108, the plate structure 94 may be fixed to thecollar 108 via an adhesive, a weld, a press fit, or a fastener toprevent rotation and axial translation of the plate structure 94relative to the collar 108. Two prongs 110 extend axially (i.e., in theaxial direction defined by the rotational axis 68) from the periphery ofthe plate 94 toward the head 90 of the hub 66. The prongs 110 arediametrically opposed from one another (i.e., antipodal points) andcorrespond to mating apertures 112 in the seed disk 54. When the prongs110 engage the apertures 112 in the seed disk 54, rotation of the seeddisk 54 results in rotation of the hub 66 and rotation of the hub 66results in rotation of the seed disk 54.

The seed disk 54 includes the seed openings 78, the apertures 112, aswell as a central mounting aperture 120 for mounting to the hub 66, andspecifically to the head portion 90 of the hub 66. The central mountingaperture 120 extends from the seed-side face 54B of the seed disk 54through to the vacuum-side face 54C, defining a channel therebetween. Asshown in FIG. 6, the diameter of the mounting aperture 120 is variablefrom the seed-side 54B to the vacuum-side 54C. More specifically, thediameter of the mounting aperture decreases (e.g., linearly,parabolically, etc.) from the seed-side 54B to the vacuum-side 54C.

Assembly of the seed meter 44 includes mounting the seed disk 54 withinthe seed disk housing 52. The bearings 68A, 68B are positioned withinthe cavity 58 in the rear side of the seed disk housing 52B and arefixed axially by a press fit, spacer, adhesive, or other fastener toprevent the outer race of the bearings 68A, 68B from rotating relativeto the seed disk housing 52. The second axial end 66B of the hub 66 isaxially inserted through the bearings 68A, 68B from an interior of theseed disk housing 52 such that the second axial end 66B passes throughboth bearings 68A, 68B. The hub 66 is fully inserted into the bearings68A, 68B when the spacer or collar 108 abuts the first bearing 68A. Withthe collar 108 positioned against the bearing 68A, the second axial end66B extends past the housing 52 a distance to permit assembly of thehandle 104 to the hub 66.

The round plate structure 94 is placed over the first axial end 66A ofthe hub 66, over the nose 90A and seated axially against the collar 108.The round plate structure 94 is fixed to the head portion 90 or thecollar 108 via a press fit, a weld, an adhesive, or another fastener(e.g., threaded fastener, rivet, etc.) such that rotation of the roundplate structure 94 rotates the collar 108 and the head portion 90.Alternatively, the round plate structure 94 may be integrally formedwith the collar 108 and would therefore not require the separate step ofassembling the plate structure 94 to the collar 108.

The ring (O-ring 98 or C-ring 100) is inserted into the annular channel96. The O-ring 98 is slid over the nose 90A and cylindrical portion 90Bof the head portion 90 and into the channel 96. The C-ring may also beaxially inserted into the channel 96 or may otherwise be elasticallyexpanded (e.g., via a tool such as a snap ring pliers) and insertedradially into the channel 96.

With the ring 98, 100 in place, the central mounting aperture 120 of theseed disk 54 is inserted onto the hub 66 over the tapered nose 90A withthe vacuum-side face 54C of the seed disk 54 in facing relation to thecollar 118, the round plate structure 94, and the vacuum side of theseed disk housing 52B. The increasing diameter of the tapered nose 90Aaids in initial placement of the seed disk 54 onto the hub 66 andcentering of the seed disk 54 relative to the hub 66. Once the centralmounting aperture 120 of the seed disk 54 clears the tapered nose 90A,it is guided along the cylindrical portion 90B of the head portion 90.At this stage, a number of alignment features are implemented tointerface the seed disk 54 with the motor output gear 70 and the hub 66.Namely, the teeth 54A of the seed disk 54 are aligned with the teeth 70Aof the motor output gear 70 (or an intermediate gear therebetween).Further, the apertures 112 in the seed disk 54 are aligned with theprongs 110 on the hub 66. Once these components are aligned, the seeddisk 66 can be axially translated along the hub 66 and over the ring 98,100.

As shown in FIG. 6, translating the seed disk 54 over the ring 98, 100includes compressing the ring 98, 100 a first amount to pass thenarrowest point of the mounting aperture 120 over the ring 98, 100. Oncepast the narrowest point, the ring 98, 100 is compressed a secondamount, less than the first amount, but great enough to maintain contactbetween with the channel 96 and the mounting aperture 120. With the ring98, 100 compressed the second amount less than the first amount, removalof the seed disk 54 requires once again compressing the ring 98, 100 thefirst amount, which can prevent accidental removal of the seed disk 54from the hub 66.

When the ring 98, 100 is compressed the second amount, the vacuum-sideface 54C of the seed disk 54 abuts against the round plate structure 94,further limiting translation of the seed disk toward the rear side ofthe seed disk housing 52B. Therefore, the ring 98, 100 and the roundplate structure 94 limit axial translation of the seed disk 54 relativeto the seed disk housing 52 and the ring 98, 100 limits radialtranslation of the seed disk 54 relative to the seed disk housing 52.Due to the interface between the apertures 112 and the prongs 110,rotation of the seed disk 54 produces similar rotation of the hub 66,and vice versa. Likewise, the interface between the teeth 54A, 70Apermits rotation of the seed disk 54 in response to actuation of themotor 72 and rotation of the motor output gear 70.

As an alternative to the ring 98, 100 and the annular channel 96, thehub 66 may include an alternative retention member. For example, theretention member may be a detent feature or spring-biased member such asa ball or a plunger that is biased radially outward from the cylindricalportion 90B of the hub 66 (i.e., at a similar axial position to theannular channel 96) by a spring. The spring biases the ball or plungerinto engagement with the central aperture 94A of the seed disk 54similar to the rings 98, 100, as discussed above. The hub may furthercomprise a button for retracting the spring to decrease or eliminate theforce provided on the aperture 94A by the spring-biased member andspring.

FIGS. 7 and 8 illustrate an interior of the seed meter 44, as viewedfrom the seed-side face 54B of the seed meter disk 54, by way of thefront housing 52A being removed. The singulator 56 and its biasingspring 202 are illustrated in the in-use position. However, it should beunderstood from FIGS. 9 to 11 that the biasing spring 202 is mounted,e.g., via a single fastener 206, to the front housing 52A that isremoved in FIGS. 7 and 8. Although further discussion of the biasingspring 202 is provided below, it is also noted here that the biasingspring 202 extends in at least two or at least three separate directionsfrom the mounting point where the fastener 206 is provided. The mountingpoint can be a central point of the biasing spring 202 as shown, withthe biasing spring 202 having two, three or more arms 202A, 202B, 202Cthat extend in a radially outward manner therefrom to individual distalends.

Turning now to FIGS. 9-12, it is shown that the singulator 56 is formedwith a cup or pocket 210 at the position of the seed meter disk centralrotation axis 68. The singulator pocket 210 receives the nose 90A of themeter hub 66. It is noted, while that the nose 90A of the meter hub 66supports the seed meter disk 54 for rotation about its central axis 68,the disk 54 is not necessarily hub-driven during operation. The radialpositioning of the singulator 56, in at least one direction, isreferenced directly from the engagement of the hub 66 with a portion ofthe singulator 56. In particular, the outer surface of the hub nose 90Ais engaged into the inner surface of the singulator pocket 210. Theradial positioning of the singulator 56 is thus fully defined by thisengagement with the hub 66. Because the seed meter disk 54 also has itsradial position referenced from the hub 66, the relative radialpositioning of the singulator 56 with respect to the seed meter disk 54is highly precise and furthermore requires no special adjustment, butrather is automatic upon installation of both the seed meter disk 54 andthe singulator 56 to the hub 66. This affords great precision in theoperation of the singulating edges or singulator “knives” in particular,which may sequentially increase in radial overlap with each seed opening78 of the meter disk 54 as it rotates past the singulator 56 for bestperformance. It should also be noted that the singulator 56, for examplethe singulator pocket 210, may have its radial position referenced inpart or in whole from a portion of the meter disk 54, which constitutespart of the meter hub 66. As such, the hub 66 is not necessarily limitedto strictly a post or shaft on which the meter disk 54 is mounted.

Turning particularly to FIGS. 13 to 15, the illustrated singulator 56includes radially outboard singulating edges or knives 214 that extendradially inward toward the path defined by the array of seed openings78. The singulator 56 also includes radially inboard singulating edgesor knives 214′ that extend radially outward toward the path defined bythe array of seed openings 78. The leading edge of each knife 214, 214′forms a knife edge that is thinnest at the initial point of contact.Each of the knife edges can be curved as shown. In the case of theradially inboard singulating knives 214′, support structures 216 and/orthe knives 214′ themselves extend toward the seed-side face 54B at orvery near to the path of a plurality of seed agitation recesses orpockets 220 formed in the seed meter disk 54 for stirring or agitatingthe seeds in the seed pool to maximize seed pick-up. As shown andlabeled in FIG. 15, chamfers 224 on the radially inboard singulatorknives 214′ allow the agitation recesses 220 to be formed as near aspossible, radially, to the seed openings 78 without “scissoring” seeds,which can lead to grinding or popping noises. By having the agitationrecesses 220 very near the seed openings 78 in the radial direction, theeffectiveness of the agitation recesses 220 is maximized.

Turning back to FIGS. 7, 8, 12, and 13, the biasing spring 202 isdescribed in further detail with respect to its placement and engagementwith the singulator 56. As mentioned briefly above, the biasing spring202 contacts the singulator 56 in multiple spaced locations. Forexample, the biasing spring 202 is forked to include three separateprongs or arms 202A, 202B, 202C that extend outwardly to define separatecontact regions with a back side 56A of the singulator 56 that isopposite a seed meter disk-facing side 56B thereof. The contact regionscorrespond to multiple contact regions between the singulator 56 and theseed-side face 54B (formed by one or more of the knives 214, 214′ andalso the surface at the end of the hub-receiving pocket 210), thusreliably maintaining the attitude of the singulator 56 with respect tothe seed meter disk 54 under the bias of the biasing spring 202 duringoperation. The first contact region, defined by the first spring arm202A, is at the position of the hub 66 along the central axis 68, wherethe singulator pocket 210 receives the hub nose 90A. In addition, thesecond and third contact regions, respectively defined by the second andthird spring arms 202B, 202C, are two circumferentially-spaced regionsproximate a radially outer portion of the singulator 56 where the knives214 or other singulating structures are located. One of these regions isfurther provided with retention geometry for positively engaging andretaining the singulator 56 to the biasing spring 202. For example, thiscan be the third contact region, which in fact, defines two separatecontact locations for exerting the axially biasing force on thesingulator 56. The third contact region as a whole is formed by twospaced-apart wings or prongs 226 of the biasing spring 202, both ofwhich are received into corresponding recesses or pockets 230 formed onthe back side 56A of the singulator 56. The pockets 230 can be formed asundercuts defining respective shoulders 230A (FIGS. 13 and 14) thatretain the biasing spring 202 by blocking the free axial removal of thebiasing spring 202 therefrom. Thus, the singulator 56 is retaineddirectly to the biasing spring 202, which is in turn fixedly secured tothe front housing 52A, by pressing the singulator 56 against the biasingspring 202 such that the third contact region is pressed into thepockets 230, the third contact region of the biasing spring 202 beingelastically deformed in the process. During assembly of the singulator56 to the biasing spring 202, the pressing of the singulator pockets230, or shoulders 230A thereof, against the prongs 226 of the biasingspring third contact region tends to induce a certain amount of axialdeflection in the biasing spring 202 since other portions of the biasingspring 202, e.g., the central portion and other arms 202A, 202B, do notdefine a resistive fit with the singulator 56 like the third spring arm202C does. To ensure that the biasing spring prongs 226 enter thecorresponding pockets 230, rather than simply deflecting the entirethird arm 202C, the front housing 52A is provided with an inwardlyextending backstop 234 as shown in FIGS. 9 and 10. The backstop 234,which is optionally formed as an integral part of the front housing 52A(e.g., single molded component), protrudes from the directly adjacentportions of the wall 236 defined by the front housing 52A. As such, thebackstop 234 provides a distal contact surface that is spaced inwardlyfrom the other surrounding portions of the front housing wall interiorsurface 236A. As such, upon pressing the singulator 56 onto the biasingspring 202, deflection of the third spring arm 202C is specificallylimited by the backstop 234 as shown in FIGS. 9 and 10, and cannot be sogreat as to reach the interior surface 236A. The backstop 234 ispositioned to be proximate or within the third contact region of thebiasing spring 202, and in particular may be between the prongs 226 asshown in the illustrated construction. Other positions and/or additionalbackstops are optional. The backstop 234 allows certainty in theposition control of the biasing spring 202 during installation of thesingulator 56 and can be used to set a desirable predetermined snap-inforce for the singulator 56 without damaging the biasing spring 202. Itis also noted that a positioning pin 238 may extend from the backstop234 in the front housing 52A to extend through a corresponding opening242 in the biasing spring 202 to define a positioning interface thatprevents the biasing spring 202 and the singulator 56 from sliding outof alignment, particularly during installation. Further, it will beappreciated that the pin 238 and the opening 242 may be reversed indefining this positioning interface.

It is noted that the illustrated biasing spring 202 is formed of asingle unitary metallic element having a variety of bends formedtherein. For example, the central portion and part of each arm 202A,202B, 202C extending therefrom can generally define a reference plane P2(FIG. 10), and distal ends of the arms forming the various contactregions can be formed by one or more bends (e.g., waves, curls, loops,etc.) that extend away from this reference plane P2. The three spacedpoints of contact between the biasing spring 202 and the singulator 56keep the singulator 56 axially referenced to the seed-side face 54B ofthe seed meter disk 54, no matter where or how the disk works.

While much of the preceding discussion focuses on the axial directionassembly features and the centering of the singulator 56 with respect tothe hub 66 and the seed meter disk 54, it must also be noted that thesingulator 56 must be held at a single fixed position about therotational axis 68 during operation while the seed meter disk 54, whichis in contact with the singulator 56, continuously rotates. The frictionbetween the seed meter disk 54 and the singulator 56 tends to urge thesingulator 56 in the rotational direction of the seed meter disk 54.However, a trailing edge of the singulator 56 with respect to therotation direction of the seed meter disk 54 defines an anti-rotationabutment surface 260 in abutment with the front housing 52A to preventrotation of the singulator 56 as the seed meter disk 54 rotates againstit. As shown in FIGS. 11 and 12, an upstanding interior wall 264projects into the cavity defined by the front housing 52A. The interiorwall 264 can be integrally formed with the front housing 52A in someconstructions, as shown, but may alternately be a separately-formedcomponent forming part of the front housing 52A when assembled. Asshown, the trailing edge of the singulator 56 is stepped so as not to belocated exclusively along one radial line.

Although knifes 214, 214′ as singulation structures have beenillustrated and described, it is also noted that alternate singulatorsaccording to the present disclosure may include one or more brushes inaddition to or in lieu of knives. FIGS. 16 and 17 illustrate one suchsingulator 286, along with a paired seed meter disk 288, for example,designed for an alternate seed type compared to that of the earlierdrawings. It will be understood that the singulator 286 and paired seedmeter disk 288 may generally correspond to the features discussed abovefor the singulator 56 and seed meter disk 54 described above including,and the above description is thus referenced for a majority of features,while the description below focuses on additional or alternate features.For example, the seed meter disk 288 of FIGS. 16 and 17 includes seedopenings 296 and agitator recesses 298, although differently configuredthan those of the seed meter disk 54. The seed meter disk 288 isprovided with a single circumferential row of seed openings 296, each ofwhich is larger than the seed openings 78 shown in FIGS. 7 and 8.Further, the seed openings 296 in the seed meter disk 288 of FIGS. 16and 17 have increased circumferential spacing as compared to the tightlyspaced seed openings 78 as shown in FIGS. 7 and 8. In someconstructions, the singulators 56, 286 and their associated seed meterdisks 54, 288 may be interchangeable within the housing 52, with thesame or alternate biasing spring 202, to reconfigure the seed meter 44for different crops.

The singulator 286 includes knives (e.g., outer and inner knives 290,290′ like those of the singulator 56) in addition to a trailing end or“last chance” brush 292, positioned opposite the leading edge of thesingulator 286 with respect to the rotation direction of the seed meterdisk 288. The brush 292 includes bristles extended toward the seed meterdisk 288. Some or all of the brush bristles may contact the seed-sideface 288B of the disk 288, although it is also considered that some orall of the brush bristles may be spaced from a seed-side face 288B. Thebrush 292, as shown, features a stepped or notched shape in which thedistal end of the brush 292 is further spaced from the seed-side face288B at a radial position of the seed openings 296. The brush 292 may bevery closely spaced to the seed-side face 288B of the seed meter disk288, or in contact therewith, at a radial position corresponding to theagitation recesses 298. It will be appreciated that a large number ofdifferent brush configurations may be desirable for use with differentcrops and thus different seed meter disks and singulators. By directlyincorporating the brush 292 into the singulator 286 (e.g., instead ofmounting the brush 292 to the housing 52), replacement of the singulator286 also automatically removes and/or replaces the brush 292 associatedtherewith, and a separate changeover is not required. It is also notedthat the singulator 286 includes a brush mounting receptacle 302, whichin the illustrated construction is provided by openings 304 through thesingulator 286 along with opposed prongs 306 arranged to grip the brush292 from two opposed sides (two prongs 306 on one side shown in FIG. 17,and two similar prongs 306, not shown, on the other side of the brush292). Although no brush is shown at the trailing end of the singulator56 of FIGS. 7 to 15, the same or similar brush mounting receptacle mayalso be provided in the singulator 56 (see FIGS. 7, 8, 11, 12, 14) foran optional brush.

As alluded to briefly above, the use of brushes in a singulator is notlimited to a notched trailing end brush. Further, a singulator for othercrop types, such as wheat, may include singulating elements consistingessentially of one or more brushes, without any knives. FIGS. 18 and 19illustrate one such singulator 316 and seed meter disk 318 combination.The seed meter disk 318 includes multiple (e.g., five) circumferentialrows of seed openings 322, and the singulator 316 includes multiple(e.g., four) brushes 326, each of which extends across multiple ones,for example all four, of the circumferential rows of seed openings 322.In addition to being spaced at unique positions along the singulator316, between its leading and trailing ends, each brush 326 is of adifferent configuration (e.g., angle orientation, spacing, if any, toseed-side face 318B of the seed meter disk 318, etc.). Each of thebrushes 326 is mounted to the singulator 316 with a brush mountingreceptacle 302 as disclosed earlier. Unlike the other singulators 56,286, that have knives in contact with the respective seed meter disks,the singulator 316 has one or more (e.g., two) seed disk referencers 330provided separately from the singulation elements to maintain a desiredattitude of the singulator 316 with respect to the seed meter disk 318under bias from the biasing spring 202. The seed disk referencers 330are rigid upstanding structures, for example having flat surfaces inabutment with the seed-side face 318B, so that the desired attitude ofthe singulator 316 is maintained, thus maintaining the predeterminedspacing (or interference) of each brush 330 with the seed-side face318B, without relying on the brushes 326 themselves to set the referenceto the seed meter disk 318. As shown, the seed disk referencers 330 areprovided radially outside the seed openings 322, but one or morereferencers can also be positioned radially inside the seed openings322. It is also noted that the portion of the singulator 316 thatreceives the hub nose 90A effectively serves as another referencer forthe singulator 316 as it is biased against the seed-side face 318B atthe center of the seed disk 318. Combinations of the various singulatorand seed meter disk features, along with modifications thereof such asthe different brush types and configurations, may be used with a varietyof different seed meter disk configurations in the construction ofvarious different types of seed meters, not limited to the specificcombinations shown herein. It will be apparent that the disclosure setsforth multiple specific operative embodiments, but not all suchcombinations, enabled by the disclosure.

FIGS. 20-23 show a seal 410 (and specifically a first flexible seal410A) for use with the seed meter 44. The seal 410 is a flexible sealand includes a first layer and a second layer. The first layer is arigid back plate 412. The second layer is a material with greatercompression and flexibility than the rigid back plate 412, such as aclosed-cell foam 414 with a wear resistant low friction plastic surface416. The second layer may be two ply having an inner compression ply 414and an outer low-friction surface 416. The flexible seal 410 may be asolid replaceable wear member. Alternatively, the flexible seal 410 maybe non-replaceable. Though described as a flexible seal 410, it shouldbe understood that only a portion of the seal 410 may be flexible(having compression) while the structure of the overall seal 410 may berigid, with only substantial flexibility in one direction (e.g.,transverse to the planar direction of the seal 410).

As shown in FIG. 21, the rigid back plate 412 may have raised portions420 that form interlocking members 422 for engaging with the front side52A of the seed disk housing 52. The interlocking members 422 of FIG. 21include a raised perimeter 420 forming a geometric shape (e.g.,rectangular, circular, two spaced apart semi-circles, etc.) that snap toengage with posts 424 (FIG. 26) on the mating surface of the seed meter44 (i.e., the front of the seed disk housing 52A) when installed. Theposts 424 may snap into the raised perimeter 420 forming the closedgeometry. Alternatively, the rigid back plate 412 may be provided withposts and the mating surface of the seed meter may include the raisedperimeter.

Alternatively, as shown in FIGS. 27-28, the rigid back plate 412 may beprovided with posts or prongs 426 that extend transverse to the plane ofthe flexible seal 410. As shown in FIG. 28 specifically, the prongs 426may be attached to or integrally formed with the rigid back plate 412.Each prong 426 extends from a base 428 at the back plate 412 to a flexportion 430 at a distal end 432. The flex portion 430 includes thin-wallsections 434 that are configured to flex when the prong 426 is axiallyinserted into an aperture (such as an aperture on the mating surface ofthe seed meter 44 (i.e., the front of the seed disk housing 52A). Oncecompressed through the aperture, the flex portion 430 can expand toprevent the prong 426 from disengaging with the aperture 430 unless apredefined axial force compresses the flex portion 430 for removal. Anadditional sealing member such as an O-ring 436 may be provided on theprong 426. Alternatively, the rigid back plate 412 may be provided withapertures and the mating surface 52A of the seed meter may includeprongs.

As a further alternative, the flexible seal 410 may be attached to themating surface (i.e., the front of the seed disk housing 52A) by analternative fastener, such as a snap fit about the perimeter of therigid back plate 412, a tongue-and-groove engagement, a threadedfastener, or an adhesive.

As shown in FIGS. 23-26, the seed meter 44 includes a front or seed sideof the seed disk housing 52A. The front side of the seed disk housing52A includes the inlet 62 for seeds to transfer from the mini hopper 50to the seed disk 54 (shown in FIG. 24), where the seeds are singulatedprior to planting. The seed meter 44 further includes the rear or vacuumside of the seed disk housing 52B. The rear side 52B is opposite thefront side 52A, and as shown in FIG. 24, supports the hub 66 about whichthe seed disk 54 rotates. Alternatively, in some embodiments, the hub 66may be supported by (mounted to) the front side 52A. The rear side 52Bfurther includes the air outlet/vacuum source 80 to retain seeds withinthe apertures 78 in the seed disk 54. Collectively, the front and rearsides 52A, 52B form the seed disk housing that includes the seed inlet62 from the mini hopper 50, the seed outlet 82 from the seed disk 54,and the air outlet/vacuum source 80.

As shown in FIG. 23, the seal 410 includes the first flexible seal 410Aand a second flexible seal 410B to collectively seal around theperimeter or periphery 438 of the front side of the seed disk housing52A. The seal 410 terminates short of a completed loop to provide anopening for the seed outlet 82. Therefore, the seal 410 extends from afirst end 450 at the seed outlet 82, along the curved length of thefirst seal 410A, along the curved length of the second seal 410B, and toa second end 452 at the opposite edge of the seed outlet 82. The secondend 452 is opposite the first end 450. If the seed outlet 82 were offsetfrom the central plane defined between the front and rear sides of theseed disk housing 52A, 52B such that the seed outlet 82 was formed fullywithin the front side of the seed disk housing 52A, the flexible seal410 could form a completed loop. As shown, the first and second flexibleseals 410A, 410B mate at a nonlinear interface 440 (e.g., chevroninterface) to reduce the potential for a leakage path at the interface440 and to prevent/prohibit expansion or alignment issues. Though shownin two components 410A, 410B, the flexible seal 410 could be formed ofmore or less pieces. Producing the flexible seal 410 with at least twocomponents 410A, 410B limits waste in manufacturing by nesting multipleseals 410A, 410B within one another when cutting from a large sheet ofmaterial.

If seeds get stuck between the seed disk 54 and the housing 52 or stuckwithin the outer teeth 54A of the seed disk 54, the seed can be groundor pulverized. This may lead to a decrease in efficiency and maydetrimentally increase friction between the disk 54 and the housing 52if seeds become jammed therebetween. The flexible seal 410 is positionedagainst the seed-side planar face 54B of the seed disk to prevent seeds,especially small seeds like canola, from slipping between the seed disk54 and the seed disk housing 52 when the seed disk is rotating. The seal410 prevents or limits seed loss around the seed disk 54. Thelow-friction surface 416 rides against the seed disk 54. Shims (notshown) may be placed on sides of the bearings 68A, 68B to set the axialposition of the seed disk 54 relative to the seed disk housing 52.However, use of the seal 410 may minimize or eliminate the need forshimming of the seed disk 54 relative to the housing 52.

FIGS. 29 through 40 illustrate a seed sensor 500 including a number offeatures that enable its mounting and use in a variety of diverseconfigurations within the construct of an agricultural work vehicle 10such as that of FIG. 1. In particular, FIGS. 29 and 34 illustrate theseed sensor 500 mounted in two different types of agricultural airseeder openers 504, 508 (or “row units”). In each case, the seed sensor500 interfaces with the seed meter 44 on the opener 504, 508, but thenature of the interface is different as discussed further below.Further, the same seed sensor 500 can also be used in an in-line sensorconfiguration where the seed sensor 500 is positioned at the connectionbetween two adjacent sections of seed hose. For example, such aconfiguration may be utilized in volumetric seeding where no device forseed metering is utilized. FIGS. 38-40 relate to such a configuration.For the purposes of this disclosure, the term “hose” may refer to hollowconduits of various types, constructions, and materials, which aresometimes referred to as “tubes” as well.

As shown in FIG. 29, the opener 504 includes an opener frame 512 thatsupports, among other things, the seed meter 44, a ground opener 514, aclosing wheel 516, and the seed sensor 500. A press wheel can beprovided between the ground opener 514 and the closing wheel 516. Theseed sensor 500 is coupled between the seed meter outlet 82 and theoutlet chute 84 (or “seed tube”). As will be discussed in further detailbelow, the seed sensor 500 includes a housing 518, a mounting structure(e.g., a bracket or loop 530, FIGS. 32 and 33), and a sensor unit (e.g.,an optical sensor unit 520, FIGS. 39-40). The seed sensor 500 is hollowto define, between respective inlet and outlet ends 501, 502, aninternal seed channel 522 defining a path for seeds to flow along acentral axis A_(s) through the seed sensor 500. As illustrated, everyseed discharged from the seed meter 44 must pass through the seed sensor500 to reach the ground furrow for seeding, and thus, the seed sensor500 operates to detect and report (i.e., to a controller 525) each andevery seed discharged from the seed meter 44 for seeding or drilling. Toprovide electrical communication from the seed sensor 500 to thecontroller 525 (and optionally to provide power to the seed sensor 500),the seed sensor 500 includes an electrical connector 528. The electricalconnector 528 can be constructed as one half of a plug-and-socket pairin which interfitting bodies (e.g., molded plug and socket bodies) arerespectively provided with conductor pins and matched conductor pinreceivers. As shown in more detail in the later figures, the illustratedelectrical connector 528 is constructed as a socket in which multipleconductor pins are housed so that a plug member having conductor pinreceivers can be received at least partially within the socket whileestablishing electrical contact between the pins and pin receivers. Inthe illustrated construction, an outer surface of the housing 518defines the electrical connector 528, e.g., as an integral portionthereof. The electrical connector 528 can be positioned adjacent theoutlet end 502 as shown. Furthermore, the electrical connector 528 canbe positioned on an opposite side of the central axis A_(s) as comparedto the mounting loop 530.

As shown in FIGS. 30-32, the seed sensor 500 is structurally adapted foruse in the opener 504, whether configured as a left-hand opener (FIG.30) or a right hand opener 504′ (FIG. 31). The openers 504, 504′ areotherwise identical, and as can be seen in comparing FIGS. 30 and 31,the seed tube 84 can be oriented at an angle α from the central fore-aftplane P3, despite the seed meter 44 and seed meter outlet 82 beingaligned with the central fore-aft plane P3. The angle α is introduced bya feature on the seed sensor 500 where it mounts to the opener frame512. As shown in FIGS. 32 and 33, the mounting loop 530 loops over anupwardly extending tongue 532 of the opener frame 512. The loop 530extends to define a plane P4 that is transverse to the central axisA_(s) through the seed sensor 500, and an opening 536 is defined throughthe loop 530 in a direction parallel to the central axis A_(s). A bottomsurface of the loop 530 includes portions 534, for example oppositelateral side portions, angled oppositely from each other at the angle α(with reference to the plane P4). As shown, a portion of the bottom loopsurface 535 between the side portions 534 can extend along the plane P4,or parallel to the plane P4, which may alternately be defined through acenter or along a top surface of the loop 530. When the seed sensor 500is mounted on the opener frame 512 with the loop 530 over the tongue532, one of the side portions 534 engages the opener frame 512 to setthe angle α of the seed sensor 500 and the seed tube 84 with respect tothe central fore-aft plane P3 to the desired side for the opener 504,depending on whether the opener 504 is configured as a left-hand openeror a right-hand opener. The angle α may take a variety of values. Insome constructions, the angle α is at least 2 degrees and not more than10 degrees. In some constructions, the angle α is at least 2 degrees andnot more than 6 degrees, and may for example be 4 degrees. The mountingof the seed sensor 500 is important in achieving the desired angularoffset of the seed tube 84 as shown in FIGS. 30 and 31 because the seedtube 84 of the opener 504 hangs from the seed sensor 500 and is notseparately mounted or fixed to the opener frame 512. For example, theupstream end of the seed tube 84 may be clamped onto the outlet end 502of the seed sensor 500. However, this is unique to the opener 504, andthe seed sensor 500 can also be used in a different type ofconfiguration within the opener 508 of FIGS. 34-37.

In the opener 508 of FIGS. 34-37, the ground opener 514′ (a hoe point inthis case, as opposed to the disk ground opener of the opener 504) isprovided with a substantial forward offset from the seed tube 84 suchthat the seed tube 84 can extend straight down from the seed meter 44.Furthermore, the opener frame 538 of the opener 508 is provided with asupport 540 that extends below the seed sensor 500 and fixes a positionand orientation of the upper end of the seed tube 84 to which the outletend 502 of the seed sensor 500 is coupled. As such, the seed sensor 500and the seed tube 84 may be devoid of a fixed connection therebetween(i.e., unsecured with no locking or clamping), other than the outlet endof the seed sensor 500 being set into and/or pressed against the seedtube 84. The connection between the seed sensor 500 and the seed tube 84is furthermore devoid of any fasteners and does not require the use oftools for connection and disconnection. The opener frame 538 includes atongue 532 like the opener 504, but the seed sensor 500 is supportedfrom below by the support 540 such that it does not hang from the tongue532 in some constructions. The seed sensor 500 may contact the tongue532 with the un-angled portion of the bottom loop surface 535 betweenthe side portions 534 in the case of the opener 508, or the loop 530 ofthe seed sensor 500 may simply pass over the tongue 532 without restingthereon. In the case of both the first and second openers 504, 508, theseed sensor 500, once mounted, provides a locating point forinstallation of the seed meter 44. In other words, the seed meter outlet82 engages with the inlet end 501 of the seed sensor 500 to properlyposition the seed meter 44 on the opener 504, 508 before the seed meter44 is ultimately secured to the opener frame 512, 538. The connectionbetween the seed meter outlet 82 and the seed sensor 500 may be devoidof a fixed connection therebetween (i.e., unsecured with no locking orclamping), other than the seed meter outlet 82 being set into and/orpressed against the seed sensor inlet end 501. The connection betweenthe seed sensor 500 and the seed meter outlet 82 is furthermore devoidof any fasteners and does not require the use of tools for connectionand disconnection.

The inlet end 501 of the seed sensor 500, which also forms the inlet endof the seed channel 522 through the sensor, is formed in the illustratedconstruction by the housing 518. Other portions of the seed channel 522,including interior to the housing 518 and down to the outlet end 502that projects outward from the housing 518 according to the illustratedconstruction are formed by a separate conduit member 544 secured withinthe housing 518. The inlet end 501 directs seeds into an upstream end ofthe conduit member 544. More particularly, an inlet section 548 of theseed channel 522 extending from the inlet end 501 tapers incross-section toward an interior of the seed sensor 500. Aspects of thecross-section of the seed channel 522 discussed herein refer tocross-sections taken perpendicular to the central axis A_(s), unlessnoted otherwise, for example, as in the cross-section taken along thecentral axis A_(s) shown in FIG. 36. The lengthwise cross-section ofFIG. 36 illustrates the shape of the taper of the inlet section 548. Thetapered inlet section 548 can form a section of a cone (i.e.,frusto-conical), a section of a sphere (i.e., frusto-spherical), or asection of a revolved parabola, for example. The surface(s) defining thetapered inlet section 548 form the receiving end of the press-in orset-in connection with the seed meter outlet 82 discussed above. Asshown in FIG. 35, a resilient member(s) 550 is provided at a location tobe elastically compressed between the opener frame 512 and the loop 530upon engagement of the seed meter outlet end 82 with the tapered inletsection 548 of the seed sensor 500. This may function to apply an upwardbias force through the seed sensor 500 to the seed meter 44 toself-align or co-align these components together automatically uponinstallation. It should be noted that the resilient member(s) 550 can beintegrated as part of the opener frame 512, the seed sensor, or may beseparate therefrom.

The tapered inlet section 548 leads toward a target viewing position 552defined by the sensor unit 520. As illustrated, the sensing unit 520 ispositioned alongside the internal seed channel 522, within the housing518, for example adjacent the conduit member 544. The sensor unit 520can include optical sensor elements on one side of the seed channel 522and one or more corresponding lighting elements on an opposite side ofthe seed channel 522. The lighting elements can emit light toward theoptical sensor elements, and the interruption of light received due topassage of seeds can be detected and conveyed to the controller 525 asthe seed count.

A cross-sectional area of the seed channel 522 at the target viewingposition 552 is greater than the area of the cross-section directlyupstream, at a downstream end of the tapered inlet section 548. From thetarget viewing position 552, the seed channel 522 tapers incross-section toward its outlet end. Moreover, it is noted that the seedchannel 522 at the location of the target viewing position 552 isflat-sided in cross-section, taken perpendicular to the central axisA_(s). This contrasts with the circular cross-section at both the inletand outlet ends 501, 502. Thus, the seed channel 522 not only changes incross-sectional area along the axial direction, but also includes atleast two regions of shape transformation—one upstream of the targetviewing position 552 and one downstream of the target viewing position552. Due to the joint construction of the seed channel 522, only part ofwhich is defined by the conduit member 544, the inlet end of the conduitmember 544 can have a flat-sided cross-section. As illustrated, thecross-section of the seed channel 522 is rectangular at both the inletend of the conduit member 544 and at the target viewing position 552just downstream.

As shown in FIGS. 38-40, a third configuration for the seed sensor 500includes an in-line configuration along a run of seed hose for example,apart from any seed meter. The seed sensor 500 in such a configurationis provided with an adapter (e.g., an inlet end adapter 566). The inletend adapter 566 has a downstream end received within the tapered inletsection 548 of the seed channel 522. The inlet end adapter 566 is asnap-on adapter that can be attached to and detached from the seedsensor housing 518 by hand, without tools. A resilient clip 570 of theinlet end adapter 566 is received by and secured with the opening 536defined by the loop 530. The inlet end adapter 566 also engages the seedsensor 500 on the opposite side from the mounting loop 530. Inparticular, a hook 572 of the inlet end adapter 566 is received by areceptacle 574 formed in the housing 518 at a position opposite the loopso that the inlet end adapter 566 can pivot about the hook 572 to slidethe resilient clip 570 through the opening 536, while simultaneouslycompressing a seal 576 of the inlet end adapter 566 into the taperedinlet section 548. In clipped engagement, opposing prongs of theresilient clip 570 engage respective retainer surfaces of the loop 530,and these retainer surfaces can be the bottom surface side portions 534that are individually angled in opposite directions with respect to thetransverse reference plane P4. The inlet end of the inlet end adapter566 is formed by a barbed stem 580 adapted for engagement with theinterior surface of a seed hose end (e.g., a 1-inch inner diameterhose). Likewise, the outlet end 502 of the seed sensor as formed by theprotruding portion of the conduit member 544 can be coupled with anotherseed hose end (e.g., by insertion into the seed hose end and/or a hoseclamp).

The seed meters 44 are mounted to a mount or mounting bracket 610 at aheight above the ground and above the ground system 38, andspecifically, the motor 72 and the seed meter housing 52 are positionedon the mount 610. With the mini-hopper 50 mounted to the seed meterhousing 52, the mini-hopper 50 is likewise positioned on the mount 610.The mount 610 is fixed relative to the ground system via a frame 612.

As shown best in FIG. 43, the mount 610 includes a meter mountingportion 614, a motor mounting portion 616, and a controller mountingportion 618. The three mounting portions 614, 616, 618 may be formed ofa single component, or may otherwise be formed by multiple componentsattached (e.g., fastened, welded) to one another. The meter mountingportion 614 extends between two frame mounting points 620A, 620B, wherethe mount 610 is fastened to the frame 612. Specifically, fasteners 622(e.g., threaded fasteners, rivets, etc.) extend through the frame 612and into the mount 610 to fix the mount 610 to the frame 612. The framemounting points 620A, 620B are axially offset from one another todistribute the holding forces in multiple planes. The location andorientation of the mounting points 620A, 620B shown in FIG. 43 furtherdictates that the meter mounting portion 618 includes a bend 626 tofacilitate alignment with the mounting points 620A, 620B.

As shown in FIG. 45, the frame 612 includes a tab 612A that extendsthrough a cutout or slot 618A in the meter mounting portion 614. The tab612A includes an aperture 612B to function as a pivot point for the seedmeter 44. More specifically, a bracket 630 is attached to the seed meterhousing 52 (the first side of the seed meter housing 52A) with fasteners632 (e.g., threaded fasteners) at a proximal end 630A and extends awayfrom the seed meter 44 to a distal end 630B defined by a pivot member634. The pivot member 634 is insertable into the aperture 612B in thetab 612A and is moveable within the aperture 612B such that the seedmeter housing 52 is rotatable about a rotational axis 636 at the pivotmember 634 between a disengaged position (FIG. 41) and an engagedposition (FIG. 42).

Referring once again to FIG. 43, the motor mounting portion 616 of themount 610 extends perpendicular from the meter mounting portion 614. Themotor mounting portion 616 includes motor mounting points (not shown)for attaching and fixing the motor 72 to the mount 610. The motormounting portion 616 further includes an aperture 638 extending throughthe motor mounting portion 616. With the motor 72 mounted to the motormounting portion 616, the output shaft of the motor 72 extends throughthe aperture 638 such that the motor output gear 70 (mounted to theshaft) is on the side of the motor mounting portion 616 opposite themotor 72. A boss feature 640 surrounds the output gear 70 and theaperture 638 and includes a non-planar engagement surface 642, whichwill be described in greater detail below with respect to FIGS. 47, 48A,and 48B.

With reference to FIGS. 42-43, the controller mounting portion 618 isperpendicular to the meter and motor mounting portions 614, 616. Acontroller 644 is mounted to the controller mounting portion 618 viafasteners 646 (e.g., threaded fasteners). The controller 644 may controlvarious aspects of the seed meter 44 such as controlling actuation ofthe motor 72 and receiving inputs from various sensors.

The seed meter housing 52 which houses the seed disk 54 is shownprimarily in FIGS. 41, 42, and 46. As discussed above, the seed meterhousing 52 includes the first and second sides 52A, 52B, which incombination with the seed disk 54 mounted therein, define first andsecond cavities 46, 48 on opposing sides of the seed disk 54. The seeddisk 54 includes radial teeth 54A that, when in the engaged position(FIG. 42) enmesh (either directly, or indirectly with one or moreintermediate gears positioned therebetween) with the teeth 70A of theoutput gear 70 (as shown in FIG. 7). The meshing interface between theseed disk 54 and the output gear 70 (and/or an intermediate gear) isdefined within the seed meter housing 52 and more specifically within ahook or hook-shaped nose 650 of the seed meter housing 52.

The hook 650 is formed with the meter housing 52 and is formed partiallyof the first side of the seed meter housing 52A and partially of thesecond side of the seed meter housing 52B. The majority of the seedmeter housing 52 (excepting for the hook 650) houses the seed disk 54 inthe first and second chambers 46, 48. The hook 650 extends from themajority of the meter housing 52 and extends from a base 652 attached tothe portion of the seed meter housing 52 defining the chambers 46, 48.The hook 650 extends from the base 652, along a curved path, to a tip654 spaced away from the base 652 and the chambers 46, 48. As shown inFIG. 42, at least the second side of the seed meter housing 52A includesa shroud 656 spanning the distance between the base 652 and the tip 654to define a chamber 658 (FIG. 48A) within the hook 650 (i.e., betweenthe tip 654 and the base 652). An opening 670 of the shroud 656 or thehook 650 allows the hook 650 to be placed over the motor output gear 70when transitioning from the disengaged position (FIG. 41) to the engagedposition (FIG. 42). Therefore the chamber 658 is in communication withan exterior of the seed meter housing 52 through the opening 670. As thechamber 658 is in communication with the chambers 46, 48 surrounding theseed disk 52, the chambers 46, 48 are likewise in communication with theexterior of the seed disk housing 52 via the opening 670.

The hook 650 includes an interior surface 660 (in facing relation withthe chamber 658) between the tip 654 and the base 652, and at least aportion of the interior surface 660 defines a non-planar engagementsurface or portion 662. The non-planar engagement surface 662 of thehook 650 interacts with and engages the non-planar engagement surface642 of the motor mount portion 616 when the seed meter 44 is in theengaged position (FIG. 42).

As shown in FIG. 48A, the non-planar engagement surface 662 of the hook650 extends from a position between the base 652 and the tip 654 to thetip 654. The engagement surface 662 follows a curved path along thelength of the hook 650 such that a thickness (as shown for example bythe thickness of the tip at measurement 664) of the portion of the hook650 partially defined by the engagement surface 662 decreases as itapproaches the tip 654. As shown, the thickness of the portion definedby the engagement surface 662 decreases monotonically from the portionof the engagement surface 662 nearest the base 652 to the tip 654.

As shown in FIG. 48B, the non-planar engagement surface 642 of the motormounting bracket 616 extends along the boss feature 640 that surroundsthe motor output gear 70. The engagement surface 642 follows a curvedpath along the boss feature 640 to a tip 668, the curved path beingformed opposite the engagement surface 662 of the hook 650. Therefore,when in the engaged position, the engagement surfaces 642, 662 mateagainst one another along the engagement surfaces 642, 662. Thenon-linear engagement ensures that the teeth 70A of the motor outputgear 70 are axially aligned with the teeth 54A of the seed disk 54.Further, as the surfaces 642, 662 are non-linear, additional rotation ofthe engagement surface 662 of the hook 650 relative to the engagementsurface 642 of the motor mounting bracket 616 results in opposing normalforces against the surfaces 642, 662 (as illustrated by arrows 666A,666B on the respective surface being acted on). The normal forces needto be overcome to disengage the surfaces 642, 662.

In addition to the engagement provided by the mating non-planarengagement surfaces 642, 662, the seed meter 44 includes a latch system672 for maintaining the seed disk housing 52 in the engaged position. Inother words, the latch system 672 maintains the intermeshingrelationship between the seed disk 54 and the motor output gear 70. Anexternal surface 674 of the hook 650 (i.e., on the first portion of theseed housing 52A) includes a second engagement surface 676 for engagingthe latch mechanism 672. Specifically, the latch mechanism 672 includesa cam 678 that is biased by a spring 680 (e.g., torsion spring) to alocked position when the seed meter 44 is in the engaged position (FIG.42). The cam 678 is attached to a lever or handle 682 and the cam/handlesystem 678, 682 is mounted to the motor mounting portion 118 with thetorsion spring 680. The handle 682 can be actuated by a user to manuallyrotate a cam surface 684 of the cam 678 out of the engaged position (inengagement with the second engagement surface 676 of the seed diskhousing 52) to a disengaged position. The handle 682 and cam 678 arebiased by the spring 680 to automatically return to the engagedposition, where the cam surface 684 rests against the second engagementsurface 676 of the seed disk housing 52.

To transition the seed meter 44 from the disengaged position (FIG. 41)to the engaged position (FIG. 42), the user rotates the seed meterhousing 52 about the rotational axis 636 defined at the pivot member 634and the tab 612A of the frame 612. The seed meter housing 52 is rotatedsuch that the motor output gear 70 is inserted through the opening 670in the shroud 656 and into the chamber 658 defined by the hook 650 andthe shroud 656. As the teeth 54A of the seed disk 54 and the teeth 70Aof the output gear 70 are rotated toward one another, the tip 654 of thehook 650 is rotated about the boss feature 640 with the non-planarengagement surfaces 642, 662 in facing relation to one another. Theteeth 54A of the seed disk 54 mesh with the teeth 70A of the output gear70 as a gap between the engagement surfaces 642, 662 decreases until theengagement surfaces 642, 662 contact one another. Further pressure canbe applied to the seed meter housing 52 (i.e., the hook 650 of the seedmeter housing 52) to increase the pressure between the engagementsurfaces 642, 662, as described above with respect to the forcesillustrated with arrows 666A, 666B.

As the seed meter housing 52 is rotated toward the engaged position, thesecond engagement surface 676 of the hook 650 contacts the cam 678. Toreach the engaged position, the seed meter housing 52 overcomes a springforce of the torsion spring 680, thereby rotating the cam 678 from thebiased position relative to the engagement surface 676 and permittingthe seed meter housing to extend past. Once in the engaged position, thecam surface 684 rotates via the torsion spring 680 to the biasedposition to hold the seed meter housing 52 in the engaged position.

To transition the seed meter 44 from the engaged position (FIG. 42) tothe disengaged position (FIG. 41), the user rotates the handle 682 todisengage the cam surface 684 from the second engagement surface 676.Then, the user is able to rotate the seed disk housing 52 about therotational axis 636 to disengage the teeth 54A of the seed disk 54 fromthe teeth 70A of the motor output gear 70.

FIG. 49 is a detail view illustrating a seed disk 754 for the seed meter44 of FIG. 2. The seed disk 754 generally conforms to the features andfunction as set forth for the seed disk 54 above, except as specificallynoted herein. Thus, reference is made to the preceding drawings anddescription for all other features of the seed disk 754. As with theseed disk 54, the seed disk 754 of FIG. 49 includes a circumferentialarray of seed openings 778 and a circumferential array of agitators inthe form of agitator pockets 720. The agitator pockets 720 are formed asdepressions in the seed-side face 754B of the seed disk 754. Suchdepressions or other agitator structures may be formed integrally as asingle piece with the body (e.g., molded plastic body) forming the seeddisk 754. Due to the rotational nature of the seed disk 754 and thepredetermined rotational direction R for the seed disk 754, eachagitator pocket 720 has a radially inner end 720A, a radially outer end720B, and a predefined forward-facing surface 725 extendingtherebetween. The term “forward-facing” is not meant to refer topositioning at a leading edge of the agitator pocket 720, and in factthe forward-facing surface 725 is positioned at the trailing edge of theagitator pocket 720. Each corresponding forward-facing surface 725 formsat least part of the trailing edge of the agitator pocket 720. Theforward-facing surface 725 is the surface that is facing toward the seedpool to engage the seeds as the seed disk 754 rotates in the rotationaldirection R. In the case of a pocket, this is the trailing edge, butother arrangements are optional, e.g., where the agitator has a formother than that shown.

At least a portion of the trailing edge of one or more of the agitatorpockets 720 among the array of seed agitator pockets 720 is backswept sothat a circumferential-direction offset O_(r) increases toward theradially outer end. The offset O_(r) is measured circumferentiallyopposite the rotational direction R as a distance from a radialreference line L_(r) rotationally ahead of the forward-facing surface725 with respect to the rotation direction R. The backswept portion ofthe forward-facing surface 725 is non-linear, although in someconstructions it may be made up of multiple linear segments. Asillustrated, the backswept portion is curvilinear, forming a smoothcurve without linear segments or sharp edges therein. In someconstructions, the backswept portion makes up the entire trailing end orthe entire forward-facing surface 725, and the entire forward-facingsurface 725 is non-linear. In combination with the backswept portion asdefined above, other portions of the forward-facing surface 725 can haveother configurations, e.g., one or more linear segments (radiallyextending or otherwise), one or more additional curved or sweptsegments, etc. In some constructions, including the illustratedconstruction, the backswept portion extends to a radially outer end ofthe forward-facing surface 725. Although all of the agitator pockets 720are shown to have identical structures, each of which has aforward-facing surface 725 with a non-linear, backswept portion, shapecharacteristics may vary among the agitators within the seed disk 754.Of course, any or all of the size, radial position, and circumferentialspacing of the illustrated agitator pockets 720 may be modified in otherconstructions. While the array of agitator pockets 720 is a ring-shapedarray in which all are positioned at a common radial offset from thecentral axis 68, other circumferential arrays may be less uniform, andmay include a subset of agitator pockets and/or other structures at atleast one different radial position.

Seed meters 44 are positioned in a vertical or upright orientation whenin use (when singulating and planting seeds) and may be rotated to anynumber of stowed positions when in transport or in storage. The arrow810 shown in FIG. 50A illustrates the upright orientation (i.e.,opposing gravity) when the seed meter 44 is in use. The arrows 812, 814shown in FIG. 51 illustrate two storage orientations in which theupright direction (i.e., opposing gravity) is transverse to the uprightdirection shown by the arrow 810 in FIG. 50A. Further positions at anangle between the arrows 810, 812, 814 shown in FIGS. 50A and 51 may befurther storage or transport positions. Regardless of the specific angleor orientation, the seed meter 44 is rotatable relative to thegravitational direction between a plurality of positions and is operableto maintain these plurality of positions (i.e., be locked into positionfor use, transport, or storage).

It is beneficial to limit the amount of rain that enters the seed meter44 (i.e., within the seed meter housing 52). Water build-up can lead todecreased efficiency of the singulating disk 54 in the singulating meter44, increased wear to moving components, and can further lead topremature germination of seeds. As such, it is likewise beneficial todrain water from within the seed disk housing 52 to prevent or limit thebuild-up of water within the housing 52. As the seed meter 44 isrotatable between various positions, rainfall can have various ingresspoints based on the orientation of the seed meter 44 relative to thegravitational direction, as described above. Therefore, devices forlimiting rain ingress for rotatable seed meters 44 require structurethat limits rain ingress in multiple orientations without detrimentallymodifying the functionality of the seed meter 44.

As shown in FIG. 51, the metering element or seed disk 54 is mountedwithin the housing 52 between the front and rear portions or sides 52A,52B of the seed disk housing 52. The seed disk 54 is rotatably mountedand axially positioned within the housing 52 on a hub 66. The hub 66 ismounted on the bearings 68A, 68B located within the housing 52 anddefines the axis of rotation 68 of the seed disk 54. The hub 66 extendsfrom the internal end 66A at the seed disk 54 to an external end 66Boutside of the seed disk housing 52. A handle 104 is fixed to theexternal end 66B such that rotation of the handle 104 rotates the hub 66and likewise rotates the seed disk 54. An operator can manually rotatethe handle 104 to check the functionality of the seed disk 54 (e.g.,check if the seed disk 54 is stuck).

FIGS. 50A, 50B, and 51 show apertures or drain holes 820 located in thehousing 52 of the seed meter 44 and specifically in the rear or vacuumside of the seed meter 52B. As shown in FIG. 50B, the drain holes 820are spaced radially about the hub 66 at even intervals. Other drain holearrangements (i.e., more or less drain holes 820, size of drain holes820, positioning of drain holes 820, etc.) may be utilized.

As shown in FIGS. 50A and 51, a vacuum cavity 822 is part of the secondcavity 48 (defined between the vacuum-side face 54C of the seed disk 54and the rear side of the seed disk housing 52B) and is defined betweentwo sidewalls 824, 826 extending axially (parallel to the rotationalaxis 68) from the rear side of the seed disk housing 52B. As shown inFIG. 51, the two sidewalls 824, 826 may be formed by a single sidewallforming a circuit. Further, a rubber seal 828 (FIG. 50A) may extend fromthe sidewalls 824, 826 to the installed seed disk 54 to seal the vacuumcavity 822. The vacuum cavity 822 is an airflow path between the seedopenings 78 of the seed disk 54 and the vacuum source/air outlet 80 tohold seeds within the seed openings 78. The drain holes 820 are locatedoutside of the vacuum cavity 822 so as to not affect the vacuum draw ofthe seed meter 44.

In the upright orientation shown in FIG. 50A, the orientation of thedrain holes 820 (transverse to the direction of rainfall or thedirection of gravity) limits the amount of water that enters the drainholes 820. Further, the drain holes 820 are positioned within bossfeatures 830 (e.g., stubs or protuberances) that extend axially outwardfrom the remainder of the seed disk housing 52 (i.e., in the axialdirection of the drain holes 820). The boss features 830 furtherredirect the rain water that streams down the outside of the seed diskhousing 52 around the drain holes 820.

In the first storage/transport orientation (shown on FIG. 51), the drainholes 820 are axially aligned with the gravitational direction. However,the handle 104 limits or prohibits rainfall from entering the drainholes 820. The handle 104 includes an umbrella dome 840 that isdome-shaped and extends over the drain holes 820 in the firststorage/transport orientation. The umbrella dome 840 directs rainfallthat impinges against the umbrella dome 840 (and would otherwise fallthrough the drain holes) to an outer edge 842, away from the drain holes820. Therefore, even in the rotated orientation in which verticalrainfall were to fall through the drain holes 820, the handle 104prohibits or limits rain ingress through the drain holes 820.

In the second storage orientation (also shown in FIG. 51), the drainholes 820 are axially aligned with the gravitational direction, but arelocated below the seed meter housing 52 (i.e., in facing relationship tothe ground). Therefore, the drain holes 820 are not in a position toreceive rainfall, but may otherwise be susceptible to spray from contactbetween a ground surface and wheels 12 (e.g., vehicle wheels, wheel fortransporting the seed meter, etc.) or the ground system 38 or splashing.The shape of the umbrella dome 840 (along with the direction ofgravitational flow of water) limits the ingress of splashed or sprayedwater into the seed disk housing 52 in the second storage/transport modeor orientation. Further, in the second storage/transport orientation,the drain holes 820 provide an outlet path for any water that is withinthe seed disk housing 52 such that seed within the mini-hopper 50 andthe seed disk housing does not sit within a pool of water. The waterfalls out the drain holes 820 and collects within the underside of theumbrella dome 840 until the water fills the hollowed dome 840 or theseed meter 44 is rotated.

If the seed meter 44 is otherwise rotated toward or away from the workvehicle 10 (i.e., about an axis parallel to the rotational axis of theseed disk), the drain holes 820 function similar to the upwardorientation shown in FIG. 50A, with the drain holes 820 still extendingtransverse to the direction of rainfall.

FIGS. 52-54 illustrate a majority of the seed meter 44 in greaterdetail, especially with respect to the seed receptacle or mini-hopper50. As described above with respect to FIGS. 2-4, the mini-hopper 50 isa housing or receptacle for storing seeds and includes the seed inlet 60for introducing seeds to the mini-hopper 50 (e.g., volumetricallymetered from a larger hopper 28), an air inlet 64 for providing airflowto produce a pressure differential to facilitate the vacuum function ofthe seed meter 44, and a seed/air outlet 62. The seed/air outlet 62(referred to as a seed outlet) is an opening in the front side of theseed disk housing 52 for introducing seeds in the mini-hopper 50 to theseed disk 54. The seed inlet 60 to the mini-hopper 50 includes a chute844 that extends downward from the wall of the mini-hopper 50 into aseed chamber 846, with a chute outlet 848 positioned at the end of thechute 844 to direct seeds to the bottom of the mini-hopper 50 (i.e.,toward the seed outlet 62 of the mini-hopper 50). The air inlet 64 ismounted to a wall of the mini-hopper 50 and is positioned above theoutlet 848 of the seed inlet chute 844.

It is beneficial to keep water out of the mini-hopper 50 to preventpremature germination of seeds within the mini-hopper 50 and to improveairflow at the seed disk 54. The air inlet 64 provides a path from theenvironment to the mini-hopper 50, and therefore is provided withstructure to limit rain ingress into the mini-hopper 50.

The air inlet 64 includes a proximal end or first end 850 for engagingthe mini-hopper, a distal end or second end 852 opposite the first end850, and a hollow air inlet boot 854 extending therebetween. Airflowinto the mini-hopper 50 through the air inlet 64 travels through anaperture 858 at the second end 852, along a channel defining an airflowpath through the air inlet boot 854, and out an aperture 856 at thefirst end 850. The first end 850 is attached (e.g., removably fixed) tothe mini-hopper 50 at the first end 850 via an interference fit, amating interface, or a fastener such as a hose clamp or an adhesive.

The boot 854 is made of a waterproof elastic substance (such as rubberor other polymer) and is stepped in size from a first cross-sectionalsize at the first end 850 of the air inlet 64 to a secondcross-sectional size at the second end 852, the second cross-sectionalsize being greater than the first. The boot 854 includes discretecross-sectional portions, similar to a step pyramid having rectangularstepped regions that increase in size monotonically. In other words, atthe second end 852 of the air inlet 64, the boot 854 includes arectangular cross-section, followed by a number (e.g., five) ofsuccessive rectangular cross-sections of increasingly diminisheddimensions, at which point the boot 854 reaches the first end 850 of theair inlet 64.

A screen 862 is positioned at the second end 852 of the air inlet 64 toprohibit or reduce the amount of dirt and debris from entering themini-hopper 50 through the air inlet 64. Further, the increasedcross-sectional area of the second end 852 (relative to the first end850) reduces the air velocity drawn into the second end 852 of the airinlet 64, decreasing the probability of large debris from suctioningagainst and covering the screen 862.

The boot 854 has a mass and elasticity that allows the air inlet 64 tosag via gravity relative to the mini-hopper 50, as denoted by arrow 874.Written another way, with the first end 850 of the boot fixed to themini-hopper 50, the second end 852 bows down relative to the mini-hopper52. Therefore, the screen 862 (covering the opening 858 at the secondend 852 of the air inlet 64) is oriented away from an upward orientationregardless of the position of the seed meter 44 (e.g., use andstorage/transport orientations shown in FIGS. 50A and 51). In otherwords, the screen 862 covering the second end 852 of the air inlet 64has an airflow intake direction (as illustrated with arrows 864)transverse to a plane 866 of the screen 862 and the airflow intakedirection 864 has an upward vertical component (i.e., opposing gravity).Therefore, rainfall is not able to fall directly into the air inlet 64through the opening 858 at the second end 852 regardless of theorientation of the seed meter 44 relative to the ground. Further, theridges or steps 870 formed by the varied cross section of the boot 854redirect the rain water that streams down the outside of the boot 854away from the second end 852.

Airflow from the boot 854 enters the mini hopper 50 through the firstend 850. The airflow path into the first end 850 is defined as beingnormal to a plane 868 defined by the opening 856 at the first end 850.The planes 866, 868 are non-parallel due to the gravitational sagging atthe second end 852 such that the planes 866, 868 intersect.

The seed meter 44 further includes additional features to limit rainingress into the seed meter 44. The mini-hopper 50 includes a lid 880that is removable to provide user access to the contents of themini-hopper 50. One example of a further feature to limit rain ingressis a foam seal 882 located between the mini-hopper lid 880 and themini-hopper 50. When the mini-hopper lid 880 is snapped into place uponthe mini-hopper 50, the foam seal 882 is compressed to form a sealtherebetween, thereby limiting rain ingress at the interface between themini-hopper 50 and the lid 880. The foam seal 882 may be attached to oneor both of the lid 880 and the mini-hopper 50 via a snap feature,adhesive, or other fastener.

The seed meter 44 of each row unit 45 has one or more hose connections,e.g., a seed hose connection at the seed inlet 60 to receive seeds to bemetered, a vacuum hose connection at the air outlet 80 to a vacuumsource (not shown), and in many cases “jumper” hose connections thatinterconnect two or more seed meters 44 of different row units 45. Forexample, the seed and/or+/±pressure source may be supplied indirectly,through an intermediate row unit 45, to some of the other row units 45.An example of this is the jumper seed outlet 60A shown in FIG.55 to bejointly formed with the seed inlet 60 so that a portion of seedsreceived by the seed inlet 60 enter into the mini hopper 50, whileanother portion of the seeds are passed through the seed outlet 60A toform a jumper circuit to another seed meter 44. These examples aremerely exemplary and it is specifically noted that other combinationsand arrangements of connections are possible, while utilizing aspects ofthe invention. It is also specifically reiterated that the seedmetering, and thus the corresponding air hose connections, may beconfigured to positively pressurize the seed side of the seed meterrather than pulling vacuum on the opposite side.

Although the above described hose connections in agricultural vehiclesare known to be tool-less, the ease of connection and disconnection byhand without tools may come at the expense of occasional nuisancedisconnections. Thus, there is a need for an improved tool-less hoseconnection in agricultural work vehicles such as the vehicle 10 of FIG.1, among others. This may be especially true as machines continue to getwider, with more row units 45 needing to be fed by so-calledSeed-On-Demand (SOD) systems. This has led to more complexity with aneed to add jumper circuits, as briefly mentioned above, in which asingle nozzle in a bulk seed tank (i.e., commodity container 28, FIG. 1)is used to provide seed flow to more than one seed meter 44. Similarly,as singulation seed-metering technology is applied to air-seeders whichtypically have many more row units, these circuits continue to becomemore complex, with many more hoses and connecting components to make theentire system work.

In typical two-piece tool-less bayonet connectors on agricultural workvehicles, one piece of the connector includes one or more 90-degreeslots or channels with closed ends, while the other piece includes acorresponding number of circular cross-section pins or pegs that arereceived within the slots. The connection is made by axial sliding ofthe two pieces together with the pins aligned with the inlets of thecorresponding slots, followed by a relative rotation about the axis sothat the pins travel circumferentially to the closed ends of thecorresponding slots. Although the general construction and assemblytechnique used by the present invention are similar to that of thetraditional bayonet connectors described above, one or both of the slotsand the pins have a unique shape as described below. The invention takesadvantage of a highly convenient tool-less coupling structure forengaging and disengaging connections by hand, while greatly reducing oreliminating nuisance disconnections. In particular, the force vectorsneeded to disconnect the components shown in FIGS. 55-59 are highlyspecific force vectors (e.g., a nearly straight axial compression vectorto compress an internal compression seal 904, or excessive rotationalforce). The same geometry also enables easy connection due to asignificant difference in mechanical advantage when rotating thebayonet-style connection in the “engage” direction vs the “disengage”direction. In describing the nature of the coupling structure orbayonet-style connection, it should be understood that these may referto any one or more of the seed outlet 60, the jumper seed outlet 60A,the air outlet 80, and/or any other tool-less coupling found on aconduit within an agricultural work vehicle including pneumatic conduitsor chemical conduits. The seed outlet 60, the jumper seed outlet 60A,and the air outlet 80 are referred to collectively as connector piecesin that they are operable to form a connection or coupling structurewith another complementary connector piece. Exemplary complementaryconnector pieces are illustrated herein as the hose connector 908 ofFIG. 56-57 and the plug connector 912 of FIG. 58.

As shown in FIG. 55, the connector pieces respectively formed by theseed outlet 60 and the jumper seed outlet 60A are each provided with atleast one pin (e.g., diametrically opposed pair(s) of pins 916 asshown). The pins 916 extend or protrude from an outer side wall of theseed outlet 60 and the jumper seed outlet 60A in a direction radiallyoutward, or transverse to a central axis defined by the conduit formedby the seed outlet 60 or jumper seed outlet 60A, respectively. The hoseconnector 908, which has a hose interface portion 918 (e.g., includingbarbed exterior surface) for insertion and retention into a hose 920 asshown in FIG. 56, is provided with at least one slot complementary tothe pin(s) 916 (e.g., diametrically opposed pair(s) of slots 924 asshown). Each slot 924 is a bayonet-type slot having an approximately90-degree slot configuration for reception of one of the pins 916 in anaxial entry direction, followed by a circumferential coupling direction.Each slot 924 includes an inlet portion 924A for receiving the pin 916in the initial axial coupling direction, prior to rotation forsecurement. The inlet portions 924A are provided at a distal end 928 ofthe hose connector 908 and extend axially therefrom. Further details ofthe slots 924 are described with reference to the detail view of FIG.59, along with FIG. 56. From the inlet portion 924A, each slot 924includes a connector portion 924B having a directional componentextending circumferentially toward a seat or receiving pocket 924C forholding the pin 916 in a secured position. The connector portion 924Bcan be at least partially defined by a first ramp comprising a flat rampsurface 930. The ramp surface 930 can be less steep in angle than aback-side ramp surface 932 leading from the first ramp surface 930 tothe receiving pocket 924C.

In particular, a first angle θ₁ is defined by the ramp surface 930 withrespect to a reference plane P9 defined by the distal end 928 of thehose connector 908. The first angle θ₁ can be substantially less than asecond angle θ₂ defined by the back-side ramp surface 932 with respectto the reference plane P9. For example, the second angle θ₂ can be atleast 1.5 times, or at least 2 times the first angle θ₁. In someconstructions, the second angle θ₂ is at least 2 times the first angleθ₁ and not more than 3 times the first angle θ₁. In some constructions,inclusive of the illustrated construction, the second angle θ₂ is over30 degrees, and the first angle θ₁ is under 30 degrees. Thus, speakingstrictly to assembly and disassembly by the exertion of relativerotation or torque (not including applied axial force), assembly torqueto seat the pins 916 can be less than a disassembly torque to unseat thepins 916 (e.g., 20 percent, 30 percent, 50 percent reduction or more)for a given compression seal 904, which is arranged to require apredetermined amount of elastic compression against an end surface 940of the connector piece during both assembly and disassembly. This meansthat the user can more readily attach the coupling than detach it byexerting rotational force. In fact, the mechanical advantage discrepancymay make it possible for the average user to be able to engage thecoupling by exerting only a rotational torque by hand, while it may beimpossible for the average user to be able to disengage the coupling byexerting only a counter-rotational torque by hand. This greatly improvesthe security of the joint against nuisance uncoupling withoutnecessitating fasteners or the use of tools. It is also explicitly notedthat the second angle θ₂ can be 90 degrees (perpendicular to the planeP9 and aligned with the central conduit axis), or over 90 degrees (i.e.,such that the back-side ramp surface 932 is “backswept” to extend downand to the left from the ramp surface 930 in FIG. 59, rather than downand to the right). Such configurations actually demand a separate axialcompression force in addition to a disengaging torque, as disengagingtorque alone does not result in the application of an axial compressionforce.

Further, each of the pins 916 has a cross-section shape that is not acircle, as is most common in most conventional couplings. In fact, thepins 916 may be non-round in cross-section (i.e., having a shape notconforming to a circle, oval, ellipse, or combinations thereof). Forexample, each of the pins 916 can have a cross-section shape thatincludes at least one flat surface and one or more edges or corners. Forexample, the illustrated pins 916 include a flat or planar surface 944Athat lies against the flat or planar back-side ramp surface 932 when thepin 916 is seated in the receiving pocket 924C. Another portion 944B ofthe pin 916, which may optionally be curved or formed to include one ormore flat surfaces, can directly abut a complementary-shaped basesurface of the slot 924, which together with the back-side ramp surface932 forms the receiving pocket 924C. Because the flat shape of theback-side ramp surface 932 matches the shape of the pin portion surface944B, these may be referred to as a surface-matched pair. In fact,multiple surface portions of the receiving pocket 924C (or the entiretyof the receiving pocket 924C) may form a surface-matched pair with thecorresponding portion(s) of the pin 916.

Although the back-side ramp surface 932 is provided for translation ofthe pin 916 during disengagement, the rotational forces fordisengagement are quite high due to the matching cross-section shapes orsurfaces therebetween, and the steep angle θ₂ of the back-side rampsurface 932. Thus, to effect disengagement, the user is to apply aseparate axial compression force between the seed inlet 60 (or otherfirst connector piece) and the corresponding hose connector 908 (orother second connector piece), bringing the first and second connectorpieces toward one another and compressing the compression seal 904,prior to or during application of a disengagement torque. As long as theuser is properly informed of the procedure, no additional hardship isenacted (e.g., such as the requirement for tools and/or additionalfastening elements), and the likelihood of an unintentionaldisengagement is greatly reduced.

It should be noted that the features described above, which at timesmake specific reference to the seed inlet 60 and the hose connector 908shown in FIGS. 57 and 59 are also applicable to other embodiments.Without duplicating the relevant description, the features describedabove with respect to the pins 916 and the slots 924 may also apply toother combinations of connector pieces. For example, the jumper seedoutlet 60A has the same arrangement of pins 916 as provided on the seedinlet 60 and discussed above. Further, a plug connection piece 950 (FIG.58) has the same arrangement of slots 924 as the slots 924 formed on thehose connector 908. The plug connection piece 950 can be an optionalaccessory for the seed meter 44 or other device, that caps off or closesthe conduit formed by the complementary connector piece (in theillustrated case the seed inlet 60) when not necessary to flow air orcommodity through it. Though not shown, the plug connection piece 950also includes the compression seal 904 as in the hose connector 908.However, in other constructions, the compression seal 904 or similarcomponent(s) may be incorporated into the opposite connector piece(i.e., the connector pieces having the pins 916, such as the seed inlet60, the jumper seed outlet 60A, or the air outlet 80). Furthermore, itis conceived that the pins 916 and the slots 924 may be exchanged,partially or fully, so that the connector pieces having the pins 916 asillustrated will include one or more slots 924, and the connector pieceshaving the slots 924 as illustrated will include one or more pins 916.Although disclosed in the context of an agricultural work vehicle, andmore particularly connections for a seed meter, features of thetool-less coupling structures disclosed may find use in a variety ofother fields of use. Even within agricultural work vehicles, thedisclosed coupling structures may find application in any one or moreof: seed hose couplings, air pressure hose couplings (pressure or vacuummeter), and fertilizer hose couplings, among others.

FIGS. 60-62 illustrate a singulator 1056 according to another embodimentof the disclosure. Each of the singulator 1056, the cooperating biasingspring 1002, and the cooperating seed meter front housing 1052A havevariations in form and function compared to those illustrated in FIGS.7-15 and described in the preceding text. However, many features andfunctions are retained and thus, the following description focuses onthe specific variations, while reference is made to the precedingdescription for features that are not specifically modified. Initially,it is noted that the biasing spring 1002 is not provided with theopening 242 for the positioning pin 238, which also is not present inthe front housing 1052A. Rather, the orientation of the biasing spring1002 with respect to the front housing 1052A is provided by one or morenotches 1003 (e.g., extended cutout(s) adjacent the central fasteningaperture of the biasing spring 1002) and one or more cooperating posts1005 of the front housing 1052A that engage into the notch(es) 1003 whenin the assembled position. Thus, the position of the biasing spring 1002can be reliably controlled, despite the biasing spring 1002 beingsecured by a single fastener 206 to the front housing 1052A. Thenotch(es) 1003 and the post(s) 1005 may be reversed in otherconstructions. Further, the backstop 234 of the front housing 52A(centrally located between the prongs 226, FIG. 9) is removed in favorof a pair of backstops 1034 that are spaced apart to overlie the biasingspring wings or prongs 1026 (of the third arm 1002C) and also thecorresponding recesses or pockets 1030 of the singulator 1056. As such,during assembly of the singulator 1056 onto the pre-assembled biasingspring 1002 in the front housing 52A, each spring prong 1026 is moredirectly backed-up or supported for obtaining a reliable engagement ofthe prongs 1026 into the pockets 1030, rather than simply deflecting theprongs 1026 of the biasing spring 1002, although inward deflection ofthe prongs 1026 toward each other occurs in order to seat the prongs1026 into their respective pockets 1030. Finally, it is noted that theremaining arms 1002A, 1002B of the biasing spring 1002 are flat and notbent or contoured to reach toward the singulator back side 1056A.Rather, the singulator 1056 is formed with extensions or protrusions1011 that extend from the back side 1056A to reach toward the planedefined by the spring arms 1002A-C. As such, the biasing spring 1002 isentirely flat or planar, with the exception of the prongs 1026.

FIGS. 63-66 illustrate a singulator 1156 according to another embodimentof the disclosure. Each of the singulator 1156, the cooperating biasingspring 1102, and the cooperating seed meter front housing 1152A havevariations in form and function compared to those illustrated in FIGS.7-15, or FIGS. 60-62 and described in the preceding text. However, manyfeatures and functions are retained and thus, the following descriptionfocuses on the specific variations, while reference is made to thepreceding description for features that are not specifically modified.Initially, it is noted that the biasing spring 1102 is not provided withprongs and the singulator 1156 is not provided with snap-in recesses forsuch prongs. In fact, the singulator 1156 of FIGS. 63-66 is notassembled to the biasing spring 1102 in a direction parallel to thecentral axis 68. As discussed below, the assembly of the singulator 1156to the biasing spring 1102 may occur in a direction perpendicular to thecentral axis 68, or particularly, a circumferential direction about thecentral axis 68. As such, there is no need for backstops 234, 1034, andsuch features are not present in the front housing 1152A. Orientation ofthe biasing spring 1102 with respect to the front housing 1152A isprovided by one or more notches 1103 (e.g., extended cutout(s) adjacentthe central fastening aperture of the biasing spring 1002) andcooperating post(s) 1105 (FIG. 65) of the front housing 1152A asdescribed above. The manufacture of the biasing spring 1102 can befurther simplified by eliminating all out-of-plane bends, resulting inthe biasing spring 1102 having a planar construction throughout allthree arms 1102A-C. However, each of the arms 1102A-C incorporatesadditional features to facilitate assembly and removal of the singulator1156 onto the biasing spring 1102. First, along the central axis 68, anopening 1159 is formed in the first spring arm 1102A to receive alocating pin 1161 that extends from the singulator back side 1156A. Thelocating pin 1161 extends from a singulator protrusion 1161A that actsas a standoff, providing a shoulder for limiting axial-directionmovement between the singulator 1156 and the biasing spring 1102 so thatthe biasing spring 1102 can transfer its biasing force to the singulator1156 through the protrusion 1161A. Similarly, the singulator 1156 isformed with extensions or protrusions 1111 that extend from the backside 1156A to contact the spring arms 1102B, 1102C. In fact, as withother embodiments, the spring arms 1102A-C are deflected, uponinstallation of the seed meter disk 54,from the point of fixture of thebiasing spring 1102 to the front housing 1152A (e.g., fastener 206) toallow biasing force to be applied to the singulator 1156 for pressing itagainst the seed meter disk 54. This is accomplished in this particularembodiment by the two protrusions 1111 and the protrusion 1161A.

With respect to FIGS. 65 (pre-assembly) and 66 (assembled), it is notedthat the biasing spring 1102 is first secured to the front housing1152A, and then the singulator 1156 is installed to the biasing spring1102 by inserting the pin 1161 through the opening 1159 at a firstrotational angle about the central axis 68 and then rotating thesingulator 1156 with respect to the biasing spring 1102 about thecentral axis 68 to a final rotational angle. In doing so, the singulator1156 automatically snaps into engagement with the biasing spring 1102.This engagement is accomplished by a bumper step 1165 of the singulator1156, which in this construction is formed integrally as an extensionwith one of the protrusions 1111. In the first rotational angle, priorto final assembly, the bumper step 1165 overlaps with the second springarm 1102B when viewed axially. Further, the bumper step 1165 extendsaxially even further beyond the protrusions 1111. Thus, pressing thebiasing spring 1102 into place axially causes a deflection of the secondspring arm 1102B (an amount greater than the operating amount). Theassembly rotation in the direction A_(D) brings the bumper step 1165 outof alignment with the second spring arm 1102B, allowing the secondspring arm 1102B to seat axially against the protrusion 1111.Optionally, a side edge of the second spring arm 1102B may be seatedagainst a side edge of the bumper step 1165. During the assemblyrotation, a protruding hook 1169 of the singulator 1156 hooks behind thethird spring arm 1102C. The protruding hook 1169 is positioned to limitthe amount of available assembly rotation of the singulator 1156 withrespect to the biasing spring 1102. The hook 1169 also prevents thesingulator 1156 from unintentionally axially sliding off the biasingspring 1102 when the seed meter is opened. Optionally, the end of thethird spring arm 1102C may also be shaped as a hook. In any case, theassembly results in the singulator 1156 being rotationally trapped tothe desired orientation with respect to the biasing member 1102 by thebumper step 1165, the hook 1169, and the second and third spring arms1102B, 1102C. In order to remove the singulator 1156 from the biasingspring 1102, the singulator 1156 is rotated opposite the assemblydirection A_(D). However, this first requires that the second spring arm1102B is deflected back in the direction D_(D) (FIG. 64) so that thebumper step 1165 can pass under the spring arm 1102B without blockingrotation of the singulator 1156. For this purpose, the second spring arm1102B can be provided with a planar extending tab 1171 to improve accesswhen assembled (FIG. 66).

FIGS. 67-70 illustrate a singulator 1256 according to another embodimentof the disclosure. Each of the singulator 1256, the cooperating biasingspring 1202, and the cooperating seed meter front housing 1252A havevariations in form and function compared to those illustrated in FIGS.7-15, FIGS. 60-62, and FIGS. 63-66, and described in the preceding text.However, many features and functions are retained and thus, thefollowing description focuses on the specific variations, whilereference is made to the preceding description for features that are notspecifically modified. Initially, it is noted that the biasing spring1202 is provided with one or more notches 1203 (e.g., extended cutout(s)adjacent the central fastening aperture of the biasing spring 1202) fororienting the biasing spring 1202 by cooperating with one or more posts1205 of the front housing 1252A, as described above. Along the centralaxis 68, at the end of the first spring arm 1202A, an opening 1259receives the pin 1261 of the singulator 1256, similar to that of FIGS.63-66. The pin 1261 extends from a singulator protrusion 1261A that actsas a standoff, providing a shoulder for contact with the first springarm 1202A. Furthermore, because the biasing spring 1202 is flatthroughout and not bent or contoured, the singulator 1256 is formed withone or more extensions or protrusions 1211 that extend from the backside 1256A to reach toward the ends of the second and third spring arms1202B, 1202C. It is shown in FIGS. 67 and 68 that the third spring arm1202C can be formed with one or more wings 1226 that extend transverselyfrom the direction of extension of the third spring arm 1202C. As shown,the end of the third spring arm 1202C is formed in a T-shape with twooppositely-extending wings 1226. The singulator protrusions 1211 for thethird arm 1202C are formed with cooperating slots 1275 that receive thewings 1226. The slots 1275 receive the wings 1226 with little or noaxial direction clearance, and are not open for assembly in a directionparallel to the central axis 68. As shown in FIG. 69 (pre-assembly) andFIG. 70 (assembled), the assembly direction A_(D) for the singulator1256 is radially outward (e.g., purely radially or at least having aradially outward component). As such, assembly of the singulator 1256 tothe pre-installed biasing spring 1202 includes assembling the singulator1256 in a first, pre-assembly position whereby the pin 1261 extendsthrough the opening 1259, with clearance, and whereby the singulator1256 is offset in a radial direction from the final assembly position.From here, the singulator 1256 is slid (e.g., radially outwardly) alongthe assembly direction A_(D) to engage the wings 1226 into the slots1275. Removal of the singulator 1256 requires sliding in a directionopposite the assembly direction A_(D) before the singulator 1256 can beaxially pulled away from the biasing spring 1202.

1. A seed metering system for metering a plurality of seeds, the seedmetering system comprising: a meter housing having a front side and arear side opposite and attached to the front side; a seed inlet definedwithin the front side of the meter housing; a seed disk positionedwithin and rotatable relative to the meter housing, the seed disk havinga first side in facing relation to the front side of the meter housingand a second side in facing relation to the rear side of the meterhousing; and a seal in contact with the front side of the meter housingand the first side of the seed disk.
 2. The seed metering system ofclaim 1, wherein the seal extends around at least a portion of aperiphery of the meter housing.
 3. The seed metering system of claim 2,wherein the meter housing includes a seed outlet, and wherein the sealterminates at the seed outlet.
 4. The seed metering system of claim 1,wherein the seal includes a first layer and a second layer, wherein thefirst layer is a rigid back plate and the second layer is a compressibleelastomeric foam.
 5. The seed metering system of claim 4, wherein theseal further comprises a low friction coating dissimilar to and adjacentthe second layer and in contact with the first side of the seed disk. 6.The seed metering system of claim 1, wherein the seed disk includes anaxis of rotation and a plurality of seed openings configured to receiveseeds from the seed inlet, and wherein the plurality of seed openingsare located radially between the axis of rotation and the seal.
 7. Theseed metering system of claim 1, wherein the seal is attachable to thefront side of the meter housing and the seed disk is rotatable relativeto the seal.
 8. The seed metering system of claim 7, wherein the sealincludes a rigid back plate with a snap engagement feature, wherein thesnap engagement feature is attachable to the front side of the meterhousing.
 9. The seed metering system of claim 8, wherein the sealfurther includes a compressible elastomeric foam layer fixed to therigid back plate.
 10. The seed metering system of claim 7, wherein oneof the seal and the front side of the meter housing includes a flexibleprong to engage with an aperture of the other one of the seal and thefront side of the meter housing.
 11. The seed metering system of claim7, wherein the seed disk is attachable to the rear side of the meterhousing.
 12. A seed meter comprising: a meter housing having a firstside and a second side opposite and attached to the front side; a seeddisk mounted within and rotatable relative to the meter housing; and aseal comprising: a first layer in contact with the first side of themeter housing; a second layer fixed to the first layer; the second layerhaving a higher compressibility than the first layer; and a low frictioncoating applied to the second layer, wherein the low friction coating isconfigured to contact the seed disk.
 13. The seed meter of claim 12,wherein the low friction coating contacts a planar face of the seeddisk, the planar face being normal to the axis of rotation of the seeddisk.
 14. The seed meter of claim 12, wherein the first layer includes asnap engagement feature configured to attach to the first side of themeter housing.
 15. The seed meter of claim 12, wherein the meter housingincludes a seed outlet, and wherein the seal includes a first endpositioned adjacent to the seed outlet and a second end positionedadjacent the seed outlet, the second end opposite the first end.
 16. Theseed meter of claim 12, wherein the seed disk is rotatable relative tothe seal.
 17. A seal for a seed meter housing, the seal comprising: arigid back plate having a first side and a second side, with anengagement feature located on the first side; and a compressibleelastomeric foam having a first side and a second side, the first sideof the compressible elastomeric foam attached to the second side of therigid back plate.
 18. The seal of claim 17, further comprising alow-friction coating applied to the second side of the compressibleelastomeric foam.
 19. The seal of claim 18, wherein the seal includes afirst seal portion having a first portion of the rigid back plate, afirst portion of the compressible elastomeric foam, and a first portionof the low-friction coating, and wherein the seal further includes asecond seal portion having a second portion of the rigid back plate, asecond portion of the compressible elastomeric foam, and a secondportion of the low-friction coating.
 20. The seal interface of claim 19,wherein the first seal portion includes a first non-linear edge and thesecond seal portion includes a second non-linear edge, wherein the firstand second non-linear edges form a mating interface.